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1

Dyulgerov, Momchil. "Potassic syenite from Shipka, Central Balkan Mts, Bulgaria: characterization and insight into the source." Geologica Balcanica 40, no. 1-3 (December 2011): 3–12. http://dx.doi.org/10.52321/geolbalc.40.1-3.3.

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Petrographic, mineralogical and whole-rock chemistry data from a new outcrop of peralkaline potassic syenite of presumed Variscan age near the town of Shipka, are presented here. The syenites exhibit peralkaline chemistry and very potassic character which markedly differs from nearby situated potassic monzonites, known as Shipka pluton. In spite of the close spatial association of these two bodies, genetic link between them can hardly be supposed. The syenites are composed of K-feldspar, diopside, mica and late interstitial amphibole. Mineral composition reflects the agpaitic conditions of crystallization with formation of sodic amphibole and K-feldspars with important Sr and Ba contents. These rocks have peralkaline wholerock chemistry, very high potassic content and extreme enrichment in LILE, LREE, Th and U. Their trace element signature and isotope characteristics are in favour of derivation from metasomaticaly enriched mantle source.
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2

Dyulgerov, Momchil, and Tanya Stoylkova. "Mineralogical and geochemical characteristics of the Sedemte Prestola potassic alkaline pluton." Geologica Balcanica 51, no. 3 (December 30, 2022): 57–69. http://dx.doi.org/10.52321/geolbalc.51.3.57.

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The Sedemte Prestola pluton is an intermediate to acid plutonic body of Variscan age (308.7 ± 9.1 Ma). Despite its small size, several petrographic varieties are present: syenites, quartzsyentes and granites. It is composed of potassium feldspar, quartz, sodic-calcic amphibole; biotite, when present, is often rimmed by amphibole or strongly altered; zircon, titanite, apatite and ilmenite are the accessory phases. The rocks display pronounced potassic character with up to 10.4 wt% K2O, peralkaline tendency, and significant trace element enrichment for REE, Zr, Th, U, and Ba. The rocks also show enriched isotopic characteristic with 87/86Sri between 0.7107 and 0.7111, and 143/144Ndi between 0.51193 and 0.51182. The geochemical features of the Sedemte Prestola pluton imply orogenic geodynamic setting of formation as a product of more primitive magma fractionation. Isotopic characteristics and high LILE, Th and U contents support the derivation from enriched mantle source – phlogopite-bearing peridotites in the spinel stability field.
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3

Rogers, N. W. "Potassic magmatism as a key to trace-element enrichment processes in the upper mantle." Journal of Volcanology and Geothermal Research 50, no. 1-2 (April 1992): 85–99. http://dx.doi.org/10.1016/0377-0273(92)90038-f.

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4

ΒΟΥΔΟΥΡΗΣ, Π. "Mineral composition of mafic minerals and ore deposition from the Kassiteres (Sappes) and Pagoni Rachi ( Kirki) porphyry Cu-Mo prospects / W. Thrace." Bulletin of the Geological Society of Greece 34, no. 3 (January 1, 2001): 1005. http://dx.doi.org/10.12681/bgsg.17138.

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The porphyry Cu-Mo mineralizations at Kassiteres and Pagoni Rachi are genetically related with dioritic to dacitoandesitic subvolcanic rocks that were and preliminary microthermometric data indicate that the hypogene mineralizations were introduced during albitic / potassic alteration of the intrusives and temperatures about 400°C from boiling magmatic-hydrothermal fluids. Electron microprobe major element analyses are presented for magmatic and hydrothermal biotites and amphiboles from both occurences. Hydrothermal biotites in the albitic / potassic zones are more magnesian than their magmatic counterparts and therefore close to phlohopite end - member composition. The amphiboles from Kassiteres range from magnesio - hornblende to actinolite, commonly within the same grain. Moreover the chemical data in both magmatic and hydrothermal biotites and amphiboles from the above two occurences indicate a Mg - and Si - enrichment and a Ti - depletion during crustallization and cooling from magmatic to late magmatic - early hydrothermal conditions. It is likely that an increase in oxyzen fugacity accompanied their chemical evolution. This oxidation trend is associated with the fluid exsolution of the magmas resulting in the development of the studied porphyry type mineralizations. Elements, which are also depleted from Mg - rich (more oxidized) amphiboles and biotites (K, Na, Fe and Ti) are partitioned in the magmatic - hydrothermal fluid phase and are responsible for the albitic / potassic altaration of both occurences.
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5

Jeffery, A. J., R. Gertisser, R. A. Jackson, B. O'Driscoll, and A. Kronz. "On the compositional variability of dalyite, K2ZrSi6O15: a new occurrence from Terceira, Azores." Mineralogical Magazine 80, no. 4 (June 2016): 547–65. http://dx.doi.org/10.1180/minmag.2016.080.018.

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AbstractThe rare potassium zirconium silicate dalyite has been identified for the first time on Terceira, Azores, within syenitic ejecta of the Caldeira-Castelinho Ignimbrite Formation. New quantitative analyses of this dalyite were combined with the small number of published analyses from various locations worldwide to evaluate the mineral's compositional variability. Additionally, solid-state modelling has been applied to assess the site allocations of substituting elements. The new analyses yield the average formula (K1.84Na0.15)∑=1.99(Zr0.94Ti0.012Hf0.011Fe0.004)∑=0.967Si6.03O15. Model results predict the placement of substituting Hf and Ti in the octahedral site, and highlight the overall complexity in the incorporation of Fe, Mg and Ba. The combined dataset reveals that dalyite found within peralkaline granites and syenites is generally defined by higher Na↔K substitution and lower Ti↔Zr substitution relative to dalyite from highly potassic rocks. The Terceira dalyite exhibits a bimodal variation in the degree of Na↔K substitution which is attributed to a K-enrichment trend induced by late-stage pore wall crystallization and albitization, coupled with the control of pore size upon the degree of supersaturation required to initiate nucleation of dalyite in pores of varying size.
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6

AKAL, CÜNEYT. "K-richterite–olivine–phlogopite–diopside–sanidine lamproites from the Afyon volcanic province, Turkey." Geological Magazine 145, no. 4 (April 24, 2008): 570–85. http://dx.doi.org/10.1017/s0016756808004536.

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AbstractMiddle Miocene volcanic activity in the Afyon volcanic province (eastern part of Western Anatolia) is characterized by multistage potassic and ultrapotassic alkaline volcanic successions. The volcanism is generally related to the northward subduction of the African plate beneath the Eurasian Plate. In Afyon, the Middle Miocene volcanic products consist of melilite leucitite, tephriphonolite, trachyte, basaltic–trachyandesite, phonolite, phonotephrite, tephriphonolite and lamproite rocks. Near-surface emplacement and relatively quiescent subaerial eruptions of lamproitic magma produced different emplacement forms such as dome/plug-shaped bodies and lava flows, showing variation in volume and texture. The mineralogical constituents of the lamproites are sanidine, olivine (77 < Mg no. < 81), phlogopite (74 < Mg no. < 78), K-richterite, clinopyroxene (74 < Mg no. < 78), with accessory apatite, calcite and opaque minerals. Afyon lamproites resemble Mediterranean-type Si-rich lamproites. Their compositional range is 50–52 wt% SiO2, 4–8 wt% MgO, and they display a typical lamproitic affinity. Chondrite-normalized REE patterns exhibit enrichment in LREE relative to HREE ((La/Yb)CN=15.3–17.0). They show extreme enrichment in LILE relative to primitive mantle values and troughs of Nb and Ti. The lamproites give a range of high initial87Sr/86Sr ratios and low143Nd/144Nd ratios. The geochemical and isotopic characteristics suggest that lamproitic magma is derived from highly metasomatized mantle. The enrichment history may include metasomatic events related to subduction, as in other active orogenic areas of the Mediterranean.
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7

Rogers, N. W., C. J. Hawkesworth, R. J. Parker, and J. S. Marsh. "The geochemistry of potassic lavas from Vulsini, central Italy and implications for mantle enrichment processes beneath the Roman region." Contributions to Mineralogy and Petrology 90, no. 2-3 (July 1985): 244–57. http://dx.doi.org/10.1007/bf00378265.

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8

do Nascimento, Aline C., Davis C. de Oliveira, Luciano R. da Silva, and Raquel Sacramento. "Magnetic Petrology of Crust- and Mantle-Derived Mesoarchean Ourilândia Granitoids, Carajás Mineral Province, Brazil." Canadian Mineralogist 60, no. 4 (July 1, 2022): 597–624. http://dx.doi.org/10.3749/canmin.2100026.

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ABSTRACT This paper presents a detailed study of magnetic petrology in crust- and mantle-derived Mesoarchean granitoids (2.92–2.88 Ga) from the Ourilândia do Norte area, which is situated in the midwestern Carajás Mineral Province, southeastern Amazonian Craton (northern Brazil). The textural aspects of opaque minerals and their relation to magnetic susceptibility (MS) were combined with the results of previous works that involve whole-rock geochemistry and mineral chemistry data to discuss the formation conditions and to correlate the MS values and opaque mineral content with the crustal input related to the source of these rocks. The Ourilândia granitoids can be divided into the following three lithological associations: (1) potassic granites represented by biotite monzogranites and high-Ti granodiorites, which both host tonalite-trondhjemite-granodiorite (TTG) affinity tonalitic xenoliths; (2) sanukitoids formed by granodiorites (equi- to heterogranular and porphyritic), with minor occurrences of tonalite, quartz monzodiorite, quartz diorite, and mafic microgranular enclaves; and (3) TTG-affinity porphyritic trondhjemite, which is represented by a small, slightly deformed stock. The cumulative frequency curve from the MS data defines three main magnetic populations as follows: (1) population A is characterized by low MS values (0.05 × 10–3 to 0.59 × 10–3 SI) formed by sanukitoid and trondhjemite rocks, which contain rare opaque minerals; (2) population B is defined by moderate MS values (0.70 × 10–3 to 1.24 × 10–3 SI) wherein sanukitoids predominate over the potassic granites while ilmenite prevails in relation to magnetite; (3) population C is represented by high MS values (1.33 × 10–3 to 17.0 × 10–3 SI) in which potassic granites and high-Ti granodiorites are predominant, in addition to the porphyritic and heterogranular sanukitoids. The Fe/(Fe + Mg) ratios in whole rock, biotite, and amphibole indicate high redox conditions for the sanukitoids and potassic granites, which are mostly above the nickel-nickel oxide (NNO) buffer (+0.5 &lt; NNO &lt; +1.9) and at or slightly below the NNO for the TTG-affinity trondhjemite (–0.5 &lt; NNO &lt; +1.0). The variation in the opaque mineral content (especially magnetite) explains in the first instance the magnetic behavior of these rocks. Furthermore, our results not only suggest that the oxidation states recorded in these granitoids are associated with the nature of their sources, but also suggest that unlike the depleted mantle (reduced in nature), the continental crust (monzogranite source) and subcontinental lithospheric mantle (the source of the sanukitoids and high-Ti granodiorite) are oxidized, while the oceanic crust (trondhjemite source) is moderately oxidized. The low MS values and the scarcity of magnetite reported for the equigranular sanukitoids and trondhjemite can be attributed to the variations in crustal input (crustal anatexis and/or mantle enrichment) in magmas that can change the overall fO2 and thereby promote differences in the Fe-Ti oxide mineral assemblage. The frequent presence of magnetite and high MS in the porphyritic sanukitoid reinforces the differences in the enrichment degree of their source in relation to other sanukitoids. The Ourilândia granitoids provided temperatures between 959 and 738 °C, with a higher water content in the sanukitoids (&gt;5%) than in the potassic granites (&lt;4%) and TTG-affinity granitoids (&lt;4%). Except for the TTG-affinity trondhjemite, which returned higher emplacement depths (580–263 MPa), the studied granitoids were emplaced under high redox conditions in the upper crust (297–80 MPa). The textural aspects of the Fe-Ti oxide minerals suggest cooling temperatures of 620 to 550 °C, as indicated by the subsolidus textures in magnetite and ilmenite (trellis ilmenite, external and internal composite ilmenite lamellae, and titanite to ilmenite and pyrite to goethite replacement) in the tardi- to postmagmatic stages.
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9

Farzaneh Farahi, Saeed Taki, and Mojgan Salavati. "Petrogenesis and tectonomagmatic setting of gabbroic rocks in the Gisel area (northern Iran)." Journal of Pharmaceutical Negative Results 13, no. 4 (October 10, 2022): 583–92. http://dx.doi.org/10.47750/pnr.2022.13.04.077.

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The Alborz-Azerbaijan magmatic zone in northern Iran is one of the important zones of magmatic activity in the Cenozoic. Lithologically, this complex consists of olivine gabbro, monzogabbro, dolerite, and gabbro with granular, intergranular, and porphyritic textures. The main phenocrysts of these rocks are clinopyroxene, plagioclase, and sometimes iddingsitized olivine. The rocks producing magma has potassic and shoshonitic nature. Enrichment in large-ion lithophile elements (LILEs), i.e., Ba, Rb, and Th, and depletion of high-field strength elements (HFSEs), i.e., Ti and Nb, in the spider diagrams are of the characteristics of subduction and active continental margin rocks. Also, these diagrams show enrichment in the light rare earth elements (LREEs) compared to heavy rare earth elements (HREEs). This feature also is representative of the rocks of subduction zones and active continental margins. The geochemical and petrogenetic studies indicate unique origin of the intrusive rocks in the study area and the role of fractional crystallization with simultaneous crustal assimilation (AFC) and magma contamination with crustal rocks in the evolution of the magma forming these rocks. This magma is obtained from the low-degree partial melting of an enriched mantle source beneath the continental lithosphere with garnet lherzolite composition at a depth of 100 to 110 km in a post-collision extensional basin.
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10

Förster, Michael W., Stephan Buhre, Bo Xu, Dejan Prelević, Regina Mertz-Kraus, and Stephen F. Foley. "Two-Stage Origin of K-Enrichment in Ultrapotassic Magmatism Simulated by Melting of Experimentally Metasomatized Mantle." Minerals 10, no. 1 (December 31, 2019): 41. http://dx.doi.org/10.3390/min10010041.

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The generation of strongly potassic melts in the mantle requires the presence of phlogopite in the melting assemblage, while isotopic and trace element analyses of ultrapotassic rocks frequently indicate the involvement of subducted crustal lithologies in the source. However, phlogopite-free experiments that focus on melting of sedimentary rocks and subsequent hybridization with mantle rocks at pressures of 1–3 GPa have not successfully produced melts with K2O >5 wt%–6 wt%, while ultrapotassic igneous rocks reach up to 12 wt% K2O. Accordingly, a two-stage process that enriches K2O and increases K/Na in intermediary assemblages in the source prior to ultrapotassic magmatism seems likely. Here, we simulate this two-stage formation of ultrapotassic magmas using an experimental approach that involves re-melting of parts of an experimental product in a second experiment. In the first stage, reaction experiments containing layered sediment and dunite produced a modally metasomatized reaction zone at the border of a depleted peridotite. For the second-stage experiment, the metasomatized dunite was separated from the residue of the sedimentary rock and transferred to a smaller capsule, and melts were produced with 8 wt%–8.5 wt% K2O and K/Na of 6–7. This is the first time that extremely K-enriched ultrapotassic melts have been generated experimentally from sediments at low pressure applicable to a post-collisional setting.
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11

Seyitoǧlu, Gürol, Duncan Anderson, Geoff Nowell, and Barry Scott. "The evolution from Miocene potassic to Quaternary sodic magmatism in western Turkey: implications for enrichment processes in the lithospheric mantle." Journal of Volcanology and Geothermal Research 76, no. 1-2 (March 1997): 127–47. http://dx.doi.org/10.1016/s0377-0273(96)00069-8.

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12

Kerrich, R., and B. J. Fryer. "Lithophile-element systematics of Archean greenstone belt Au–Ag vein deposits: implications for source processes." Canadian Journal of Earth Sciences 25, no. 6 (June 1, 1988): 945–53. http://dx.doi.org/10.1139/e88-095.

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Potassic alteration domains of greenstone belt lode gold deposits are characterized by systematic partitioning between lithophile elements. K, Rb, and Ba are generally co-enriched and linearly correlated over almost three orders of magnitude in abundance, where K/Rb = 220–400 and K/Ba = 30–85; K/Cs (~104) and K/Tl (~2 × 104) are also correlated, though more weakly. Lithium abundances and Rb/Sr ratios are erratic in altered rocks. These interelement trends, collectively, are present in deposits variously hosted by ultramafic, mafic, or felsic volcanic rocks and sediments or granitoids. Magmatic processes involving crystal fractionation of biotite, K-feldspar, and plagioclase generate trends to systematically diminished K/Rb (≥50), K/Li, K/Cs, and K/Tl but enhanced K/Ba (≤8 × 103) and Rb/Sr in most late-stage differentiates. Such "late-stage" trends are the rule in "magmatophile" deposits, including the Archean Cadillac molybdenite deposit, Phanerozoic Cu- and Mo-"porphyry" deposits, Sn–W greisens, and most pegmatites. Accordingly, magmatic processes of this type can be ruled out as the dominant source of volatiles for gold-forming systems. The compliance of K/Rb and K/Ba ratios in potassic alteration domains of Au deposits with values characteristic of main-trend igneous rocks, or "average" crust, implies that K, Rb, and Ba were partitioned into the hydrothermal ore-forming fluids in approximately the same ratios as in the source rocks. Dehydration reactions in the source rocks or equilibration of fluids with source rocks under conditions of low water/rock ratio, rather than magmatic processes, may satisfy the requirement for proportional K, Rb, and Ba co-enrichment.
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13

Redin, Yury O., Anna A. Redina, Viktor P. Mokrushnikov, Alexandra V. Malyutina, and Vladislav F. Dultsev. "The Kultuma Au–Cu–Fe-Skarn Deposit (Eastern Transbaikalia): Magmatism, Zircon Geochemistry, Mineralogy, Age, Formation Conditions and Isotope Geochemical Data." Minerals 12, no. 1 (December 22, 2021): 12. http://dx.doi.org/10.3390/min12010012.

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The Kultuma deposit is among the largest and most representative Au–Cu–Fe–skarn deposits situated in Eastern Transbaikalia. However, its genetic classification is still a controversial issue. The deposit is confined to the similarly named massif of the Shakhtama complex, which is composed mainly of quartz monzodiorite-porphyry and second-phase monzodiorite-porphyry. The magmatic rocks are characterized by a low Fe2O3/FeO ratio, low magnetic susceptibility and belong to meta-aluminous, magnesian high-potassic calc-alkalic reduced granitoids of type I. The results of 40Ar-39Ar and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U-Pb dating showed that the formation of magmatic rocks proceeded during the Late Jurassic time: 161.5–156.8 Ma. Relatively low Ce/Ce*, Eu/Eu* and Dy/Yb ratios in the zircons indicate that the studied magmatic rocks were formed under relatively reduced conditions and initially contained a rather low amount of magmatic water. A mineralogical–geochemical investigation allowed us to outline five main stages (prograde skarn, retrograde skarn, potassic alteration, propylitic (hydrosilicate) alteration and late low-temperature alteration) of mineral formation, each of them being characterized by a definite paragenetic mineral association. The major iron, gold and copper ores were formed at the stage of retrograde skarn and potassic alteration, while the formation of polymetallic ores proceeded at the stage of propylitic alteration. The obtained timing of the formation of retrograde skarn (156.3 Ma) and magmatic rocks of the Shakhtama complex, along with the direct geological observations, suggest their spatial–temporal and genetic relationship. The data obtained on the age of magmatic rocks and ore mineralization are interpreted as indicating the formation of the Kultuma deposit that proceeded at the final stages of collision. Results of the investigation of the isotope composition of S in sulfide minerals point to their substantial enrichment with the heavy sulfur isotope (δ34S from 6.6 to 16‰). The only exclusion with anomalous low δ34S values (from 1.4 to 3.7‰) is pyrrhotite from retrograde skarns of the Ochunogda region. These differences are, first of all, due to the composition of the host rocks. Results of the studies of C and O isotope composition allow us to conclude that one of the main sources of carbon was the host rocks of the Bystrinskaya formation, while the changes in the isotope composition of oxygen are mainly connected with decarbonization processes and the interactions of magmatic fluids, host rocks and meteoric waters. The fluids that are responsible for the formation of the mineral associations of retrograde skarns and the zones of potassic alteration at the Kultuma deposit were reduced, moderately hot (~360–440 °C) and high-pressure (estimated pressure is up to 2.4 kbar). The distinguishing features of the fluids in the zones of potassic alteration at the Ochunogda region are a lower concentration and lower estimated pressure values (~1.7 kbar). The propylitic alteration took place with the participation of reduced lower-temperature (~280–320 °C) and lower-pressure (1–1.2 kbar) fluids saturated with carbon dioxide, which were later on diluted with meteoric waters to become more water-rich and low-temperature (~245–260 °C). The studies showed that the main factors that affected the distribution and specificity of mineralization are magmatic, lithological and structural–tectonic ones. Results of the studies allow us to classify the Kultuma deposit as a Au–Cu–Fe–skarn deposit related to reduced intrusion.
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14

Kushch, L. L., V. A. Makrygina, L. F. Suvorova, and A. V. Oshchepkova. "Origin of Skarns at Migmatization on Ol’khon Island, Lake Baikal, Russia." Геохимия 64, no. 2 (March 15, 2019): 168–81. http://dx.doi.org/10.31857/s0016-7525642168-181.

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Migmatites on the western shore of Ol’khon Island host unusual rocks: zoned lenses of hedenbergite–garnet–epidote–anorthite metasomatites coupled with the migmatites. No intrusive granites were found nearby. The skarn-forming process operated at the interface of the granite gneiss and skarn protolith (perhaps, carbonate rocks). The composition of the metasomatites is analogous to that of calcic skarns with high Al2O3, FeO, and CaO concentrations. The compositions and relations of the minerals provide evidence of the successive development of the hedenbergite–anorthite outer zone, dominantly anorthite–garnet main zone, and quartz-enriched inner zone, with all of the zones parallel to contact with the granite gneiss. The granite gneiss itself is also likely of metasomatic nature, as follows from its supraeutectic concentration of potassic feldspar in the leucosome and low crystallization temperatures. A minimum of the Gibbs free energy (calculated with the SELECTOR-C program package) was reached at 8 kbar and temperatures of 600– 625°C. These parameters are lower than the melting temperature of the granite eutectic, and the absence of melt is confirmed by the absence of melt inclusions in minerals of the granite gneisses. This indicate that the driving force of the process was migmatizing silicic–potassic solutions. The P–T parameters of the skarns are close to the foregoing values. The very high Sr and Ca and low Mg concentrations suggest that the protolith of the skarns was calcite marble. The enrichment of the skarns in the granitophile elements suggests that the skarns were produced simultaneously with and in genetic relation to the migmatization processes. The metasomatites were formed before the partial melts were derived, early in the course of the granite-forming processes and provide important information for better understanding the metasomatic process responsible for the exchange of chemical elements between the rocks.
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Cooper, Alan F., Lorraine A. Paterson, and David L. Reid. "Lithium in carbonatites — consequence of an enriched mantle source?" Mineralogical Magazine 59, no. 396 (September 1995): 401–8. http://dx.doi.org/10.1180/minmag.1995.059.396.03.

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AbstractThe rare Li-mica taeniolite is described from the Dicker Willem carbonatite complex, Namibia, and from the Alpine carbonatitic lamprophyre dyke swarm at Haast River, New Zealand. At Haast River, taeniolite occurs in sodic and ultrasodic fenites derived from quartzo-feldspathic schists and rarely in metabasites, adjacent to dykes of tinguaite, trachyte and a spectrum of carbonatites ranging from Ca- to Fe- rich types. In Namibia, taeniolite is present in potassic fenites derived from quartz-feldspathic gneisses and granitoids at the margin of an early sövite phase of the complex and in a radial sövite dyke emanating from this centre.The occurrence of taeniolite in these totally disparate carbonatite complexes, together with examples of lithian mica from other carbonatite complexes worldwide, raises the question of the status of Li as a ‘carbonatitic element’. We argue that lithium is not a consequence of crustal assimilation or interaction, but reflects the geochemical character of the magmatic source. Li, an overlooked and little-analysed element, may be an integral part of metasomatic enrichment in the mantle, and of magmas derived by partial melting of such a source.
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16

Byrne, Kevin, Guillaume Lesage, Sarah A. Gleeson, Stephen J. Piercey, Philip Lypaczewski, and Kurt Kyser. "Linking Mineralogy to Lithogeochemistry in the Highland Valley Copper District: Implications for Porphyry Copper Footprints." Economic Geology 115, no. 4 (June 1, 2020): 871–901. http://dx.doi.org/10.5382/econgeo.4733.

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Abstract The Highland Valley Copper porphyry deposits, hosted in the Late Triassic Guichon Creek batholith in the Canadian Cordillera, are unusual in that some of them formed at depths of at least 4 to 5 km in cogenetic host rocks. Enrichments in ore and pathfinder elements are generally limited to a few hundred meters beyond the pit areas, and the peripheral alteration is restricted to narrow (1–3 cm) halos around a low density of prehnite and/or epidote veinlets. It is, therefore, challenging to recognize the alteration footprint peripheral to the porphyry Cu systems. Here, we document a workflow to maximize the use of lithogeochemical data in measuring changes in mineralogy and material transfer related to porphyry formation by linking whole-rock analyses to observed alteration mineralogy at the hand specimen and deposit scale. Alteration facies and domains were determined from mapping, feldspar staining, and shortwave infrared imaging and include (1) K-feldspar halos (potassic alteration), (2) epidote veins with K-feldspar–destructive albite halos (sodic-calcic alteration), (3) quartz and coarse-grained muscovite veins and halos and fine-grained white-mica–chlorite veins and halos (white-mica–chlorite alteration), and two subfacies of propylitic alteration comprising (4) prehnite veinlets with white-mica–chlorite-prehnite halos, and (5) veins of epidote ± prehnite with halos of chlorite and patchy K-feldspar. Well-developed, feldspar-destructive, white-mica alteration is indicated by (2[Ca-C] + N + K)/Al values &lt;0.85, depletion in CaO and Na2O, enrichment in K2O, and localized SiO2 addition and is spatially limited to within ~200 m of porphyry Cu mineralization. Localized K2O, Fe2O3, and depletion in Cu, and some enrichment in Na2O and CaO, occurs in sodic-calcic domains that form a large (~34 km2) nonconcentric footprint outboard of well-mineralized and proximal zones enriched in K. Water and magmatic CO2-rich propylitic and sodic-calcic–altered rocks form the largest lithogeochemical footprint to the mineralization in the Highland Valley Copper district (~60 km2). Calcite in the footprint is interpreted to have formed via phase separation of CO2 from a late-stage magmatic volatile phase. Several observations from this study are transferable to other porphyry systems and have implications for porphyry Cu exploration. Feldspar staining and shortwave infrared imaging highlight weak and cryptic alteration that did not cause sufficient material transfer to be confidently distinguished from protolith lithogeochemical compositions. Prehnite can be a key mineral phase in propylitic alteration related to porphyry genesis, and its presence can be predicted based on host-rock composition. Sodic-calcic alteration depletes the protolith in Fe (and magnetite) and, therefore, will impact petrophysical and geophysical characteristics of the system. Whole-rock loss on ignition and C and S analyses can be used to map enrichment in water and CO2 in altered rocks, and together these form a large porphyry footprint that extends beyond domains of enrichment in ore and pathfinder elements and of pronounced alkali metasomatism.
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Galanopoulos, Evangelos, Panagiotis Voudouris, Constantinos Mavrogonatos, Paul Spry, Craig Hart, Vasilios Melfos, Federica Zaccarini, and Dimitrios Alfieris. "A New Porphyry Mo Mineralization at Aisymi-Leptokarya, South-Eastern Rhodope, North-East Greece: Geological and Mineralogical Constraints." Geosciences 8, no. 12 (November 24, 2018): 435. http://dx.doi.org/10.3390/geosciences8120435.

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A new porphyry Mo prospect has been discovered in the Aisymi-Leptokarya area, along the southern margin of the Byala Reka–Kechros metamorphic dome, south-eastern (SE) Rhodope metallogenic zone. The study area is dominated by an Oligocene felsic dike complex, which hosts the porphyry Mo mineralization and intrudes into upper Eocene sandstones-marls and the Leptokarya monzodiorite pluton. The Aisymi-Leptokarya felsic dike complex displays a rhyodacitic to dacitic composition with post-collisional affinities. The porphyry Mo mineralization occurs in the form of porphyry-style quartz stockworks in the felsic dike complex associated with potassic alteration characterized by hydrothermal K-feldspar. The ore minerals consist mainly of pyrite, molybdenite, kesterite, bismuthinite and galena within both the stockwork and the rock matrix. Bulk ore analyses indicate enrichment in Mo (up to 215 ppm), Se (up to 29 ppm), Bi (up to 8 ppm) and Sn (up to 14 ppm) in the porphyry quartz veins. Late-stage, north-east (NE-) and north-west (NW-)trending milky quartz intermediate-sulfidation epithermal veins with base metals, crosscut previous vein generations and are characterized by Ag, Sn and Te anomalies. The Aisymi-Leptokarya porphyry Mo prospect is set in a back-arc geotectonic regime and shares similarities to other post-subduction porphyry molybdenum deposits elsewhere.
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18

Witt, W. K. "Porphyry intrusions and albitites in the Bardoc–Kalgoorlie area, Western Australia, and their role in Archean epigenetic gold mineralization." Canadian Journal of Earth Sciences 29, no. 8 (August 1, 1992): 1609–22. http://dx.doi.org/10.1139/e92-127.

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Minor intrusions in the Menzies – Kambalda greenstone belt of the Archean Eastern Goldfields Province, Western Australia, range from quartz–feldspar porphyry to plagioclase–hornblende porphyry. The porphyries display enrichment of mobile and incompatible elements (K to Zr) and depletion of relatively compatible elements, with negative Nb, P, and Ti anomalies, on mid-ocean-ridge basalt-normalized spidergrams. The composition and timing of emplacement of the porphyries are consistent with a genetic relationship with spatially related granitoids. Porphyries occur in 30% of gold mines in the Menzies–Kambalda belt. The association appears to be largely structural, since both the intrusions and the mineralizing fluids exploit zones of weaknesses, such as lithological contacts and shear zones. Porphyries have been modified to varying degrees by hydrothermal alteration, especially pervasive albitization. Textural evidence indicates that secondary albite and associated sodic amphibole formed late in the deformation history of the greenstones and were broadly contemporaneous with secondary phyllosilicate, carbonate and sulphide minerals related to gold mineralization. Recent studies in the Alleghany district of California suggest the initial rock composition may critically influence the nature of alteration associated with gold mineralization. Therefore, albitization of porphyries may be caused by the same hydrothermal fluids that deposit gold and produce potassic alteration in mafic rocks.
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19

Mavrogonatos, Constantinos, Panagiotis Voudouris, Jasper Berndt, Stephan Klemme, Federica Zaccarini, Paul G. Spry, Vasilios Melfos, et al. "Trace Elements in Magnetite from the Pagoni Rachi Porphyry Prospect, NE Greece: Implications for Ore Genesis and Exploration." Minerals 9, no. 12 (November 24, 2019): 725. http://dx.doi.org/10.3390/min9120725.

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Magnetite is a common accessory phase in various types of ore deposits. Its trace element content has proven to have critical implications regarding petrogenesis and as guides in the exploration for ore deposits in general. In this study we use LA-ICP-MS (laser ablation-inductively coupled plasma-mass spectrometry) analyses of trace elements to chemically characterize magnetite from the Pagoni Rachi Cu–Mo–Re–Au porphyry-style prospect, Thrace, northern Greece. Igneous magnetite mostly occurs as euhedral grains, which are commonly replaced by hematite in fresh to propylitic-altered granodiorite porphyry, whereas, hydrothermal magnetite forms narrow veinlets or is disseminated in sodic/potassic-calcic altered (albite + K-feldspar + actinolite + biotite + chlorite) granodiorite porphyry. Magnetite is commonly associated with chalcopyrite and pyrite and locally exhibits martitization. Laser ablation ICP-MS analyses of hydrothermal magnetite yielded elevated concentrations in several trace elements (e.g., V, Pb, W, Mo, Ta, Zn, Cu, and Nb) whereas Ti, Cr, Ni, and Sn display higher concentration in its magmatic counterpart. A noteworthy enrichment in Mo, Pb, and Zn is an unusual feature of hydrothermal magnetite from Pagoni Rachi. High Si, Al, and Ca values in a few analyses of hydrothermal magnetite imply the presence of submicroscopic or nano-inclusions (e.g., chlorite, and titanite). The trace element patterns of the hydrothermal magnetite and especially the decrease in its Ti content reflect an evolution from the magmatic towards the hydrothermal conditions under decreasing temperatures, which is consistent with findings from analogous porphyry-style deposits elsewhere.
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20

Gibson, S. A., R. N. Thompson, O. H. Leonardos, S. E. Turner, J. G. Mitchell, and A. P. Dickin. "The Serra do Bueno potassic diatreme: a possible hypabyssal equivalent of the ultramafic alkaline volcanics in the Late Cretaceous Alto Paranaίba Igneous Province, SE Brazil." Mineralogical Magazine 58, no. 392 (September 1994): 357–73. http://dx.doi.org/10.1180/minmag.1994.058.392.02.

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AbstractCretaceous, strongly alkaline mafic igneous provinces occur around the margins of the Ordovician to Cretaceous Paraná sedimentary basin of southern Brazil. The Serra do Bueno diatreme is situated in the southern portion of the largest of these alkaline provinces, the Alto Paranaíba Igneous Province in Minas Gerais. The well-exposed diatreme crops out close to the south-west surface limit of the São Francisco craton and is adjacent to several other poorly exposed ultramafic alkaline pipes, previously described variously as kimberlites (Barbosa, 1991) and lamproites (Ramsay and Tompkins, in press). The diatreme has two distinct facies: (1) a crater facies dominated by lapilli tuffs; and (2) a magmatic hypabyssal facies formed by a relatively fresh ultramafic (MgO = 15 wt.%) potassic (K2O/Na2O = ∼ 1.5) intrusion that contains xenoliths of meta-sediments, feldspathic gneiss and dunite. It is massive and porphyritic, with large olivine phenocrysts (Fo87) and smaller crystals of diopside (Ca50Mg44Fe6), phlogopite, perovskite, ilmenite and zeolites in a fine-grained groundmass that contains altered leucite and up to 20% devitrified glass. The Serra do Bueno intrusion shows a strong enrichment in light relative to heavy rare earth elements, with La/Yb of ∼85. Its initial 87Sr/86Sr (0.705176) and 143Nd/144Nd (0.512312) isotopic ratios are similar to those of other intrusions (e.g. Limeira 2) and lavas (e.g. Presidente Olegário) in the Alto Paranaíba Igneous Province. This suggests that these Late Cretaceous alkaline magmas were all derived from a similar source, predominantly within the subcontinental lithospheric mantle.Laser 40Ar/39Ar analyses have yielded an isochron of 90 ± 4 Ma for the Serra do Bueno intrusion. This age is higher than the corresponding K/Ar bulk-rock age for the same sample but similar to K/Ar ages determined on mica separates from both intrusive and extrusive rocks in the Alto Paranaíba Igneous Province.
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21

Assylkhankyzy, A., G. Seitmagzimova, and I. Petropavlovsky. "ОПТИМИЗАЦИЯ ПРОЦЕССА ОБОГАЩЕНИЯ КАЛИЙНОЙ РУДЫ МЕСТОРОЖДЕНИЯ ЧЕЛКАР." Herald of Kazakh-British technical university 18, no. 1 (March 1, 2021): 39–47. http://dx.doi.org/10.55452/1998-6688-2021-18-1-39-47.

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В статье рассмотрены результаты исследования процесса переработки отмытой ка- лийной руды месторождения Челкар с целью получения безбалластного калийного удобрения. Изучена эффективность двух- и трехкратной отмывки руды от солей натрия для определения оптимально- го режима обогащения руды по калию. Установлено, что целесообразно проводить двукратную от- мывку руды промывной водой, при которой обеспечивается максимальное содержание в руде калия и минимальное содержание солей натрия. Эффективность отмывки подтверждается результатами рентгенографического анализа руды после второй отмывки. Прокалка руды приводит к дегидрата- ции кристаллогидратов минералов и возрастанию содержания в ее составе основных компонентов. Растворение прокаленной руды при температурах 50 и 90°С приводит лишь к частичному переходу в раствор солей калия и магния при полном растворении остаточного количества солей натрия. Для достижения полного растворения сульфатов калия и магния, являющихся целевыми компонентами для получения минерального удобрения, требуется изучить химические методы превращения.
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22

Lotfi, Mohammad, Mansoureh Shirnavard Shirazi, Nima Nezafati, and Arash Gourabjeripour. "MINERALOGY AND GEOCHEMISTRY STUDY OF REE MINERALS IN HOST ROCKS IN IIC IRON DEPOSIT, BAFGH MINERAL AREA, CENTRAL IRAN." Geosaberes 11 (January 8, 2020): 51. http://dx.doi.org/10.26895/geosaberes.v11i0.909.

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The IIC deposit area to the east of the Bafq region exposes rocks that comprise the part of the Central Iran continental terrane. The IIC deposit iron orebodies are magmatic-related hydrothermal deposits that, when considered collectively display a vertical zonation from high-temperature, magmatic ± hydrothermal deposits emplaced at moderate depths (~1–2 km) to magnetite-dominant IOCG deposits emplaced at an even shallower subvolcanic level. The shallowest parts of these systems include near-surface, iron oxide-only replacement deposits, surficial epithermal sediment-hosted replacement deposits, and synsedimentary (exhalative) ironstone deposits. Alteration associated with the IOCG mineralizing system within the host volcanic, plutonic, and sedimentary rocks dominantly produced potassic with lesser amounts of calcic- and sodic-rich mineral assemblages. Our data suggest that hydrothermal magmatic fluids contributed to formation of the primary sodic and calcic alterations. The aim of this study is to delineate and recognize the different iron mineralized zones, based on surface and subsurface study. However, the data do not discriminate between a magmatic-hydrothermal source fluids resolved from Fe-rich immiscible liquid or Fe-rich silicate magma. Iron ores, occurring as massive-type and vein-type bodies are chemically different. Minor pyrite occurs as a late phase in the iron ores. The REE patterns of the mineralized metasomatites show LREE enrichment and strong Eu negative anomalies. The strong negative Eu anomaly probably indicates near-surface fractionation of alkali rhyolites involving feldspars. Field observations, ore mineral and alteration assemblages, coupled with lithogeochemical data suggest that an evolving fluid from magmatic dominated to surficial brine-rich fluid has contributed to the formation of the IIC deposit.
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23

Christy, A. G., and K. Gatedal. "Extremely Pb-rich rock-forming silicates including a beryllian scapolite and associated minerals in a skarn from Långban, Värmland, Sweden." Mineralogical Magazine 69, no. 6 (December 2005): 995–1018. http://dx.doi.org/10.1180/0026461056960304.

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AbstractWe report preliminary petrographic and mineral chemical data for a rock hosting an unusual mineral assemblage from Långban, Värmland, Sweden. The rock is a two feldspar-scapolite-spessartine-romeite skarn. The bulk composition and high degree of enrichment in Pb, Sb and As suggest that the rock was formed by reaction between a pre-existing Mn skarn containing the chalcophiles and a potassic granite, with loss of silica, alkalis and CO2. The alkali feldspar is a Pb-rich hyalophane, averaging Or63Ab19Cs15Pb03, the plagioclase feldspar a Pb-rich labradorite, An48Ab48Or02Pb02, and the scapolite a 'mizzonite' (Ca/(Na+Ca) = 0.66—0.70). These minerals show their highest Pb contents recorded in nature to date: up to a maximum of 5.7 wt.% PbO in the hyalophane, 2.1% PbO in the plagioclase, and 5.3% PbO in the scapolite. Laser ablation ICP-MS of a scapolite grain detected substantial Be up to 1.7 wt.% BeO (0.6 Be per 12 tetrahedral cations), as well as Pb up to 7.05 wt.% PbO. The Be is incorporated into scapolite via the coupled exchange [Be(OH)][Al(CO3,SO4)]—1. This is the first documentation of scapolite as the major repository for Be in a rock.The romeite also contains substantial Pb, and shows extensive solid solution towards end-members containing Fe3+, Ti and Sb3+. In some analyses, the dominant end-members are and its Pb analogue rather than (Ca,Pb)2Sb2O7. Complex exsolution textures are displayed in the hyalophane, by hancockite-epidote, romeite-bindheimite and hedyphane-johnbaumite. Ca-rich scapolite and hancockite appear to be new minerals for the Långban deposit.The mineralogy appears consistent with the regional peak conditions of P = 3 kbar, T > 600°C. Several potential thermobarometers for Mn-rich skarns are identified in this rock.
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24

Yang, Mimi, Fufeng Zhao, Xianfan Liu, Hairuo Qing, Tsilavo Raharimahefa, and Wenjing Duan. "Petrogenesis and geodynamic setting of granitoids at Machangqing Cu–Mo (Au) deposit, western Yangtze craton, southwestern China: constraints from zircon U–Pb and molybdenite Re–Os geochronology, Lu–Hf isotopes, and geochemistry." Canadian Journal of Earth Sciences 57, no. 9 (September 2020): 1066–88. http://dx.doi.org/10.1139/cjes-2019-0124.

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The Machangqing Cu–Mo (Au) deposit is located in the central part of the Jinshajiang – Red River belt in the Sanjiang orogen, which lies across the Qiangtang terrane and western Yangtze craton, southwestern China. Zircon U–Pb dating constrains that the granite porphyry and porphyritic granite emplacements occurred at 35.92 ± 0.31 Ma and 34.92 ± 0.31 Ma, respectively. The Re–Os model ages of molybdenite are 34.94 ± 0.38 Ma. The new ages presented here, along with previously published data in the region, define a short duration of potassic magmatism and mineralization from 37 Ma to 34 Ma in the Jinshajiang – Red River belt. Zircon Ce4+/Ce3+ values of the porphyritic granite and granite porphyry vary from 50.32 to 1579.20 (averaging 481.01) and 33.18 to 1511.80 (averaging 452.98), respectively, and the log(fo2) values vary from –6.66 to −23.86 and −9.88 to −25.18, respectively, which plot within the range of the fayalite–magnetite–quartz buffer curve to the magnetite–hematite buffer curve, indicating an oxidized magma source, which may have facilitated the Cu–Au enrichment. Zircons from granitoids show εHf(t) values ranging from −0.75 to +2.33 and crustal model ages between 0.9 and 1.1 Ga. The features of Lu–Hf isotopes and wide range of Mg#, Cr, and Ni contents imply that the magmas of the Machangqing granitoids were probably derived from partial melting of juvenile lower crust and mixed with some mantle melts. Combined with the features of the Machangqing granitoids, the following evolution process are concluded. During the Cenozoic, the India–Asia continental collision triggered upwelling of hot asthenosphere and underplating of the thickened juvenile lower crust, which caused the formation of mafic and felsic magmas. Those magmas ascended, mixed, crystallized, and formed Machangqing ore-bearing granitoids in an intracontinental extension setting.
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25

Gettings, M. E. "Multifractal magnetic susceptibility distribution models of hydrothermally altered rocks in the Needle Creek Igneous Center of the Absaroka Mountains, Wyoming." Nonlinear Processes in Geophysics 12, no. 5 (June 10, 2005): 587–601. http://dx.doi.org/10.5194/npg-12-587-2005.

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Abstract. Magnetic susceptibility was measured for 700 samples of drill core from thirteen drill holes in the porphyry copper-molybdenum deposit of the Stinkingwater mining district in the Absaroka Mountains, Wyoming. The magnetic susceptibility measurements, chemical analyses, and alteration class provided a database for study of magnetic susceptibility in these altered rocks. The distribution of the magnetic susceptibilities for all samples is multi-modal, with overlapping peaked distributions for samples in the propylitic and phyllic alteration class, a tail of higher susceptibilities for potassic alteration, and an approximately uniform distribution over a narrow range at the highest susceptibilities for unaltered rocks. Samples from all alteration and mineralization classes show susceptibilities across a wide range of values. Samples with secondary (supergene) alteration due to oxidation or enrichment show lower susceptibilities than primary (hypogene) alteration rock. Observed magnetic susceptibility variations and the monolithological character of the host rock suggest that the variations are due to varying degrees of alteration of blocks of rock between fractures that conducted hydrothermal fluids. Alteration of rock from the fractures inward progressively reduces the bulk magnetic susceptibility of the rock. The model introduced in this paper consists of a simulation of the fracture pattern and a simulation of the alteration of the rock between fractures. A multifractal model generated from multiplicative cascades with unequal ratios produces distributions statistically similar to the observed distributions. The reduction in susceptibility in the altered rocks was modelled as a diffusion process operating on the fracture distribution support. The average magnetic susceptibility was then computed for each block. For the purpose of comparing the model results with observation, the simulated magnetic susceptibilities were then averaged over the same interval as the measured data. Comparisons of the model and data from drillholes show good but not perfect agreement.
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Tzortzakis, N. G. "Potassium and calcium enrichment alleviate salinity-induced stress in hydroponically grown endives." Horticultural Science 37, No. 4 (November 3, 2010): 155–62. http://dx.doi.org/10.17221/1/2010-hortsci.

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Salinity either of soil or of irrigation water causes disturbance in plant growth and nutrient balance and reduces crop yields. The effects of NaCl salinity and/or calcium or potassium level on the plant growth and severity of gray mold (Botrytis cinerea [De Bary] Whetzel) were investigated in endive (Cichorium endivia L., cv. Green Curled) grown with the nutrient film technique under greenhouse conditions during early spring. Plants were supplied with nutrient solutions containing 40 mmol/l of sodium chloride (NaCl) and/or 10 mmol/l potassium sulphate (K<sub>2</sub>SO<sub>4</sub>). Additionally, plants treated with foliar spray of 15 mmol/l calcium nitrate [(CaNO<sub>3</sub>)<sub>2</sub>] or distilled water. Salinity or K- and Ca-enrichment mainly affected the upper part of endive plants and reduced leaf area. However, when salinity combined with either K- or Ca-enrichment, the negative impact of salinity on plant growth was reversed. Salinized and/or K- and Ca-enriched, plants did not differ in plant biomass, leaf/root ratio, leaf fresh weight, leaf number, and root length. Salinity did not have any impacts on photosynthetic rate, stomatal conductance, and intercellular CO<sub>2</sub> concentration. Indeed, photosynthetic rate and stomatal conductance increased with Ca foliar application and decreased with K while the opposite effects were observed for the intercellular CO<sub>2</sub> concentration. Total nutrient uptake was reduced 2-fold in salt-treated plants compared to controls. No symptoms of tip-burn or blackheart were recorded throughout the experimental study. Endive grown in the nutrient film technique had tolerance to NaCl salinity, and this method could be used to exploit saline water in soilless culture. These findings also suggest that a proper management of the salt concentration of the nutrient solution plus external elemental enrichment may provide an efficient tool to improve the quality of leafy vegetables with little effect on yield.
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27

Lou, Pengcheng, Zhongying Miao, Mianping Zheng, Xuefei Zhang, Zhuang Ruan, and Qihui Xu. "Paleogeographic Characteristics of the Mengyejing Formation in the Simao Basin during Its Depositional Period and Its Indication of Potash Mineralization: A Case Study of MZK-3 Well." Minerals 11, no. 4 (March 24, 2021): 338. http://dx.doi.org/10.3390/min11040338.

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In China, pre-Quaternary solid potash deposit has only been discovered in the Simao Basin, and the Lower Cretaceous Mengyejing (MYJ) Formation (Fm.) is the productive layer of potash deposit. In this study, we investigated the clay conglomerates which are distributed in upper and lower members of the potash-bearing salt rock layer. We analyzed the relative contents of major elements (Al2O3, Fe2O3T, MgO, CaO, Na2O, K2O) and trace elements (B, Ba, Co, Cr, Cu, Ga, Mn, Ni, Rb, Sr, V, Zn, Zr) in the samples. The results show that MgO and CaO in the major elements are rich relative to Post Archean Australian Shale (PAAS), whose average enrichment factor values of the MgO (EFMgO) is 2.61 and CaO (EFCaO) is 4.57, and the others major elements are relatively minor; trace elements (B, Ga, Mn, Zr) are rich relative to PAAS, and the others trace elements are minor relative to PAAS. The study of paleogeographic conditions using various parameters shows that the paleoclimate is generally dry and hot during the period of clay conglomerate deposition, but it was warm and humid in certain periods; the main sedimentary environment is weak oxidation condition with strong oxidation conditions in individual periods; the average value of paleosalinity is ~21‰, and the highest is no more than ~92‰. The significance of the paleogeographic characteristics of MYJ Fm. to potash mineralization are as follows: (1) they indicates that the clay conglomerates of MYJ Fm. are not clastic sediments in brine formed by seawater, because the paleosalinity of clay conglomerates deposition period is obviously lower than that of seawater; (2) MYJ potassic salt ore is not formed by evaporation and concentration of seawater in clay conglomerates in the sedimentary basin, because there is no carbonate rock and sulfate rock of corresponding scale after the deposition of clay conglomerates in the basin; (3) clay conglomerates of MYJ Fm. were deposited in continental shallow water basin; (4) the matter source of potash minerals is deep marine strata; (5) in the MYJ Fm. sedimentation period, deep source salt moved to the surface under the background of extensional structure, and the subsequent sedimentary clastic rock formed a protective layer of potash-bearing rock, thus completing the “deep source and shallow mineralization” metallogenic process.
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28

Brugger, J., J. Ogierman, A. Pring, H. Waldron, and U. Kolitsch. "Origin of the secondary REE-minerals at the Paratoo copper deposit near Yunta, South Australia." Mineralogical Magazine 70, no. 6 (December 2006): 609–27. http://dx.doi.org/10.1180/0026461067060361.

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AbstractThe Paratoo copper deposit, located in the Neoproterozoic to Cambrian Adelaide Geosyncline, South Australia, produced around 360 tons of Cu between 1888 and 1967 from oxidized ores. The deposit is located in the core of a breached, doubly plunging anticline, near a zone of disruption containing brecciated Adelaidean sedimentary rocks and dolerite (‘Paratoo Diapir’), and hosted in dolomitic shales of the Neoproterozoic Burra Formation. Near the surface, the mineralization resides mainly in deeply weathered quartz-magnetite-sulphide (pyrite, chalcopyrite) veins (⩽10 cm wide). At depth, drill cores reveal disseminated magnetite, pyrite, chalcopyrite, copper sulphide and native copper associated with extensive potassic alteration. K-Na-rich fluids also affected the dolerite in the ‘Paratoo diapir’, resulting in the precipitation of K-feldspar, dravite and K-bearing chabazite-Na. The most likely scenario for the genesis of the Paratoo deposit involves circulation of basinal fluids, focusing into the ‘Paratoo Diapir’, and ore precipitation through neutralization by fluid-rock interaction with the dolomitic shales hosting the mineralization.The Paratoo deposit is deeply weathered, with malachite and chrysocolla (± tenorite and cuprite) containing the bulk of the copper recovered from the shallow workings. A diverse assemblage of secondary REE-bearing carbonate minerals, including the new species decrespignyite-(Y) and paratooite-(La), is associated with the weathered base metal and magnetite ores. Whole-rock geochemical analyses of fresh and mineralized host rock and of vein material reveals that the mineralization is associated with a strong, albeit highly variable, enrichment in light rare earth elements (LREE). This association indicates that REE and base metals were introduced by the same hydrothermal fluid. The strong negative Ce anomaly found in secondary REE minerals and mineralized rock samples suggests an upgrade of the REE contents in the weathering zone, insoluble Ce4+ being left behind.The Fe-oxide-REE-base metal association at Paratoo is also characteristic of the giant Mesoproterozoic Fe oxide copper gold deposit of Olympic Dam, located 350 km to the NW. A similar association is found in the Palaeozoic deposits of the Mt Painter Inlier, 300 km to the NNE. The widespread occurrence of this elemental association in the Province probably reflects the geochemistry of the basement, which contains numerous Mesoproterozoic granites enriched in REE and U.
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Kerrich, R. "Source processes for Archean Au–Ag vein deposits: evidence from lithophile-element systematics of the Hollinger–McIntyre and Buffalo Ankerite deposits, Timmins." Canadian Journal of Earth Sciences 26, no. 4 (April 1, 1989): 755–81. http://dx.doi.org/10.1139/e89-062.

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Potassic alteration domains of Archean greenstone belt lode gold deposits, typified by the Hollinger–McIntyre and Buffalo Ankerite mines, Timmins, are characterized by systematic partitioning between different groups of incompatible elements such that Al, Ga, Th, U, Ti, and V are decoupled from K, Rb, Ba, Li, Cs, and Tl. The former group of elements has concentrations and interelement ratios in alteration domains that reflect host-rock control, implying approximately isochemical behaviour. In contrast, the lithophile elements K, Rb, and Ba are generally coenriched and are linearly correlated over three orders of magnitude in abundance, where K/Rb = 230–380 (r = 0.92–0.99) and K/Ba = 34–97 (r = 0.82–0.99), values close to average crustal ratios of 285 and 36, respectively. K/Rb and K/Ba ratios trend towards higher values with respect to increasing concentrations of Rb and Ba, possibly because of mixing between host rock and hydrothermal reservoirs of the lithophile elements. Cs and Tl contents average 1.4 and 1.1 ppm, respectively, such that K/Cs and K/Tl, as well as K/Rb and K/Ba, trend to higher than bulk crustal ratios, signifying a mafic to ultramafic source variably depleted in Cs, Tl, Rb, and Ba relative to K. Lithium is generally not coenriched with K but rather correlates with Mg content, reflecting the primary magmatic substitution of Li1+ for Mg2+ in the parent magmas. Al and Ga are highly correlated: Al/Ga = 2070–3790 and r = 0.85–0.98. Accordingly, Al and Ga were not fractionated during mineralization. These interelement trends, collectively, are present in deposits variously hosted by ultramafic, mafic, or felsic volcanic rocks and by sediments or granitoids.Magmatic processes involving crystal fractionation of biotite, K-feldspar, and plagioclase generate trends to systematically diminished K/Rb (≥50), K/Li, K/Cs, and K/Tl but enhanced K/Ba (≤8 × 103) and Rb/Sr ratios in most late-stage differentiates. Al/Ga ratios diminish systematically during late-stage magmatic evolution, and Th–U and Ti–V display mutual partitioning governed by crystallization of trace phases. Such "late-stage" trends are the rule in "magmatophile" deposits, including the Archean Cadillac molybdenite deposit, Phanerozoic Cu- and Mo-"porphyry" deposits, Sn–W greisens, and most pegmatites. Accordingly, magmatic processes of this type can be ruled out as the dominant source of volatiles for gold-forming systems. There is no complementarity between large-ion lithophile-element (LILE) (K, Rb, Ba, Cs, U, Th) depletion patterns in granulites and K, Rb, and Ba enrichment in Au deposits. The enhanced K/Rb, K/Cs, and Rb/Cs ratios but diminished K/Ba ratios, characteristic of many granulites, are not reflected in the gold deposits, where K/Rb and K/Ba ratios approximate average crustal values and Th and U behave isochemically. In many granulites, especially Archean examples, LILE depletion is a primary feature; accordingly, the granulitization model for Au–Ag vein deposits can also be ruled out.The compliance of K/Rb and K/Ba ratios in potassic alteration domains of Au deposits with values characteristic of main-trend igneous rocks or "average" crust implies that K, Rb, and Ba were partitioned into the hydrothermal ore-forming fluids in approximately the same ratios as in the source rocks, consistent with known fluid–mineral distribution coefficients. Dehydration reactions in dominantly mafic to ultramafic source rocks under amphibolite-facies conditions or equilibration of ore-forming fluids with source rocks under conditions of low water/rock ratio, rather than either purely magmatic or granulitization processes, may satisfy the requirement for proportional K, Rb, and Ba coenrichment, Li retention, and the absence of Al–Ga fractionation.
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30

Taylor, Ryan D., Anjana K. Shah, Gregory J. Walsh, and Cliff D. Taylor. "Geochemistry and Geophysics of Iron Oxide-Apatite Deposits and Associated Waste Piles with Implications for Potential Rare Earth Element Resources from Ore and Historical Mine Waste in the Eastern Adirondack Highlands, New York, USA." Economic Geology 114, no. 8 (December 1, 2019): 1569–98. http://dx.doi.org/10.5382/econgeo.4689.

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Abstract The iron oxide-apatite (IOA) deposits of the eastern Adirondack Highlands, New York, are historical high-grade magnetite mines that contain variable concentrations of rare earth element (REE)-bearing apatite crystals. The majority of the deposits are hosted within sodically altered Lyon Mountain granite gneiss, although some deposits occur within paragneiss, gabbro, anorthosite, or potassically altered Lyon Mountain granite gneiss. The IOA deposits and the waste and/or tailings piles associated with them have potential as an unconventional resource for REEs. Reprocessing of these piles would have the advantage of partial recycling of the waste material to produce a set of critical elements. Thirty-four ore, nine rock, 25 waste-pile, and four tailings-pile samples were collected and analyzed for major, minor, and trace elements. At the tailings- and waste-pile sites, composite samples were collected by combining 30 to >50 subsamples randomly distributed over each pile. The total REE content of the waste and tailings piles varied from approximately 10 to 22,000 ppm, whereas the ore sample concentrations ranged from approximately 15 to 48,000 ppm total REEs. A positive correlation exists between the total REE content of ore and its associated waste pile. Median light REE/heavy REE values were 2.14 for waste/tailings piles and 2.25 for ore, which is a substantial relative enrichment in the heavy REEs in comparison to many developed REE mines, such as the mined carbonatites of Bayan Obo, China, and Mountain Pass, California. Importantly, the ore and waste samples are significantly enriched in both Y and Nd compared to other REEs in the samples. Other minor components such as Th are also elevated. Airborne radiometric surveys show large positive eTh and eU anomalies corresponding to tailings piles. Although it is a limited data set, geochemical data of unaltered and altered host rocks suggest a speculative new model for IOA ore formation in the Adirondack Highlands that is consistent with the geology and previously published data. The ferroan ore-hosting Lyon Mountain granite gneiss underwent localized potassic alteration that enriched the altered rock in Fe, REEs, Th, and other metals. A later sodic alteration event affected the previously potassically altered Lyon Mountain granite gneiss, which increased rock porosity and remobilized Fe, REEs, and other elements from the host rock into the iron ore seams. The sodic fluids responsible for ore formation were enriched in F and Cl.
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31

Wu, Tsai-Way, and Robert Kerrich. "Combined oxygen isotope – compositional studies of some granitoids from the Grenville Province of Ontario, Canada: implications for source regions." Canadian Journal of Earth Sciences 23, no. 9 (September 1, 1986): 1412–32. http://dx.doi.org/10.1139/e86-134.

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Oxygen isotopic compositions of whole rocks and coexisting quartz–feldspar pairs have been determined for nine pre-, and syn- to late-kinematic granitoid plutons in the Grenville Province of Ontario. These new data demonstrate that granitoid rocks (Algonquin, Mulock) in migmatite terrain of the Ontario Gneiss Segment possess normal δ18O values (<9.0‰), whereas mesozonal to epizonal plutons (Elphin, Coe Hill, Deloro, Barber's Lake) in the Central Metasedimentary Belt (CMB) are characterized by significantly higher 18O contents (δ18O > 9.0‰), in accord with previous results.In the Algonquin sodic suite, a gross covariance of δ18O with compositional indices is present, from 6.4‰, SiO2 = 50.5 wt. % (gabbro) to 8.7‰, SiO2 = 72 wt. % (trondhjemite), resulting from combined assimilation–fractional crystallization. Mafic members of the sodic suite are 18O enriched overall (5.8–7.9‰) relative to fresh tholeiites (5.7 + 0.3‰), implicating some 18O contamination of the protolith. The dispersion of δ18O values in the Algonquin potassic suite, from 4.3 to 9.3‰, is independent of composition and attributed to isotopic exchange with low-18O thermal waters during emplacement. Biotite–hornblende granite of the Mulock batholith is characterized by a limited oxygen isotope compositional range, where the average δ18O = 8.1 ± 0.5‰; δ18O correlates with SiO2 but not with the zonal distribution of Ba, Rb, and Sr abundances.The Union Lake quartz diorite (δ18O = 8.5 ± 0.1‰) and White Lake trondhjemite (δ18O = 7.3 ± 0.6‰) have oxygen isotope compositions comparable to those of other trondhjemitic suites in the CMB. A systematic enrichment of ~1.2‰ in the Union Lake pluton, together with enhanced Ca, Mg, Fe, and Sr, can be accounted for by assimilation of ~5% marbles and 10% amphibolites from the country rock. Uniformly high δ18O values of 11.5 ± 0.8‰ characterize the Elphin granite–syenite complex. The largest values (11.7–12.7‰) and lowest SiO2 (54–56 wt. %) are in the partially assimilated host gabbro–diorite complex, endorsing the presence of 18O-enriched source regions. The Cheddar biotite–hornblende granite, one of a population of intrusions within the alkalic belt of the western CMB, has a restricted isotopic span, where δ18O = 8.8 ± 0.9‰. An unusual concave rare-earth-element (REE) distribution may result from interaction with a heavy rare-earth -element (HREE) enriched volatile phase. The Coe Hill biotite granite (δ18O = 10.4 ± 0.4‰) is isotopically in compliance with other granites and syenites of the CMB. Covariance of δ18O and SiO2, in conjunction with smooth and continuous geochemical trends, is interpreted in terms of assimilation–fractional crystallization.Peralkaline granite of the Deloro pluton includes a hypersolvus phase with high, scattered δ18O values (9.1–11.8‰) and a subsolvus counterpart attributed to late influx of water that induced isotopic reequilibration toward a more constrained range (δ18O = 9.2–10.2‰). REE distributions of a calcic syenite phase are compatible with its evolution by fractional crystallization of a low-K tholeiitic magma, and the high-18O character (δ18O = 11.1–12.6‰) requires 18O enrichment of the protolith and (or) 18O contamination of the magma. Peralkaline rhyolitic volcanics, compositionally coherent with the Deloro pluton and possibly representing extrusive equivalents, possess significantly higher and more variable δ18O values, from 11.7 to 14.2‰; this is attributed to 18O enrichment during low-temperature exchange with thermal waters, superimposed on a primary high-18O magma. The Barber's Lake two-mica granite contains enhanced abundances of U (15 ppm) and Th (36 ppm) in conjunction with systematically elevated δ18O values (10.4 ± 0.5‰). Geochemical constraints are compatible with its evolution from a trondhjemitic magma, but the isotopically enriched nature requires extensive 18O contamination of the protolith and (or) magma. These nine granites variously retain "memory" of primary and (or) secondary features, including δ18O of the source region, covariance of isotopic and compositional parameters, and sporadically superimposed disturbance by exchange with thermal waters. During metamorphism, quartz and feldspar were systematically reset to high-temperature fractionations, but the extent of open-system exchange with rock reservoirs was limited.Despite some probable disturbance by metamorphism and the limited data available, O–Sr isotope systematics of the Grenville granitoids indicate that (1) high-18O granites from the Frontenac Axis were derived from in situ anatexis of Grenville Supergroup metasediments, (2) synkinematic granites were derived by mixing of a primary magma generated at a lower crustal (granulite facies) or upper mantle level with the fusion products generated by partial melting of the Archean–Early Proterozoic type metasediments, and (3) the tonalite–trondhjemite suite in this part of the Grenville Province was derived from a similar lower crustal or upper mantle primary magma by direct fractional crystallization.
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32

Seitmagzimova, Galina, Aigerim Assylkhankyzy, Almagul Kadyrbaeva, and Roza Abisheva. "ANALYSIS OF THE ENRICHMENT PROCESS OF NATURAL POTASSIUM SALTS." Rasayan Journal of Chemistry 15, no. 01 (2022): 586–92. http://dx.doi.org/10.31788/rjc.2022.1516681.

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Potassium-magnesium ores of the Chelkar deposit in Kazakhstan have a complex mineralogical composition and contain soluble sodium salts, which are an impurity component in the processing of ore into potassium fertilizers. In this regard, enrichment of natural potassium salt by incomplete dissolution was studied. Based on the experimental results the optimal washing mode was determined which ensures maximum removal of sodium salts from the natural salt composition and minimal losses of potassium salts with washing water. Mathematical models of the process under study were obtained through statistical processing of the experimental data. The results have shown that statistically, reliable regression equations are ones that describe potassium and sodium content in the solid phase relative to the process duration and water consumption for washing. The models can be used to operate the potassium ore enrichment process and to predict dependencies under various process conditions. 3D visual analysis of the process using regression surfaces for all significant equations has revealed the relationship between potassium ore enrichment indicators and process parameters.
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33

Yanez-Pizana, A., D. Mota-Rojas, M. Castillo-Rivera, R. Rampirez-Necoechea, I. Guerrero-Legarreta, P. Mora-Medina, and M. Gonzalez-Lozano. "Effect of environmental enrichment on weaned piglets: physiological responses." Veterinární Medicína 64, No. 5 (May 28, 2019): 217–27. http://dx.doi.org/10.17221/104/2018-vetmed.

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The aim of this research consisted in assessing the effect of various kinds of environmental enrichment (EE) on the physiological responses of weaned piglets. The mean age of the 96 piglets that participated was 27 days. The piglets were weaned and then housed under two conditions: with no disruption of the social order (SO), and with disruption of the social order (DSO). After establishing the two experimental conditions, we proceeded to evaluate four different treatments; namely, control (C), suspended ropes (SR), aromatized bottles (AB) and pet toys and balls (PTB). The protocol required drawing three blood samples: at 30 (T<sub>30</sub>), 60 (T<sub>60</sub>) and 90 min (T<sub>90</sub>) after weaning. The DSO piglets had higher pH and haematocrit levels than those weaned in the SO condition (P &lt; 0.05). Also, pCO<sub>2</sub>, potassium (K<sup>+</sup>) and base excess (BE) concentrations were higher in the SO animals than in those in the DSO group (P &lt; 0.05). The control piglets, which did not receive any type of EE, showed higher pCO<sub>2</sub> levels, but lower glucose and pH (P &lt; 0.05) values, while the ones enriched with SR had increased lactate levels, but lower values for pH and HCO<sub>3</sub><sub>–</sub> compared to the piglets in the other EE treatment regimens (P &lt; 0.05). The SR-enriched piglets had higher lactate and haematocrit levels, but lower values for pH and bicarbonate (HCO<sub>3</sub><sub>–</sub>) than the animals in the other EE groups (P &lt; 0.005). The piglets subjected to sensorial EE with AB had higher plasma glucose than the ones in the other groups (P &lt; 0.005). Finally, the PTB-enriched subjects showed higher Na<sup>+ </sup>levels than controls (P &lt; 0.005). The alterations that were found to be related to the factor sampling time were more pronounced at T<sub>30</sub> (P &lt; 0.05) than T<sub>60</sub> and T<sub>90</sub>. These results indicate that the conditions (SO, DSO) and EE (C, SR, AB, PTB) under which the piglets were weaned influenced the blood variables measured in the study.
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34

Valizadeh, Reza, Mohammad Ali Norouzian, Fereydoon Azizi, Mehdi Hedayeti, Abbas Ali Naserian, and Fereydoon Eftekhari Shahroodi. "Enrichment of cow milk by feeding potassium iodide." Proceedings of the British Society of Animal Science 2007 (April 2007): 187. http://dx.doi.org/10.1017/s1752756200020901.

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Iodine is an essential dietary element for mammals, required for the synthesis of the thyroid hormones; thyroxin (T4, 3,5,3’,5’-tetraiodothyronine), and its active form T3 (3,5,3’-triiodothyronine) (SCF,2002). Thyroid hormones play a major role in the growth and development of brain and central nervous systems, control of several metabolic processes in body including carbohydrate, fat, protein, vitamin and mineral metabolism (EFSA, 2005). Milk and dairy products are an important source of iodine for human. Iodine concentration of cow milk can be influenced by its concentration in the diet or pasteurization process. A Linear correlation between iodine content of the diet and concentration in cow milk has been reported (Hemken; 1979, Fish & Swenson; 1982, Lysbet et. al, 2003). This study was conducted in order to increase the iodine concentration of cow milk in accordance with human requirements by examining (i) inclusion rate of iodine in the animals diet and (ii) the effect of pasteurization process.
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35

Hutcheon, I., J. Bloch, and S. Modus. "Potassium enrichment in shale—fluid transport or provenance?" Journal of Geochemical Exploration 69-70 (June 2000): 17–22. http://dx.doi.org/10.1016/s0375-6742(00)00047-9.

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36

Wang, Xiaozhe, Zhiwu Yan, Rongrong Wang, Donghui Liu, Jianliang Zhang, and Zhengjian Liu. "Study of the enrichment characteristics of sinter by alkali metal vapors." Metallurgical Research & Technology 115, no. 3 (2018): 310. http://dx.doi.org/10.1051/metal/2018014.

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The existence forms and distributions of potassium (K) and sodium (Na) in sinter were studied by simulating the actual situations of K and Na cycle and enrichment in the blast furnace (BF). The results show that the K and Na vapor reacted with the main phase of the sinter and formed two “enrichment layers” in periphery, then the sinter samples were analyzed by means of XRD and SEM. The analysis results indicate that the main phases in light “enrichment layer” are K and Na compounds (ferrite, silicates and aluminates), iron oxide (Fe2O3) and silico-ferrite of calcium and aluminum (SFCA); while the dark “enrichment layer” mainly exists the potassium and sodium oxides. In addition, the adsorption of the sinter on K and Na vapor is the mixed adsorption of chemical and physical, and the chemical adsorption is the main adsorption method.
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37

Antonowicz, Józef Piotr, Jacek Kubiak, and Sylwia Machula. "Macroelements in the surface microlayer of water of urban ponds." Limnological Review 16, no. 3 (March 1, 2016): 115–20. http://dx.doi.org/10.1515/limre-2016-0012.

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Abstract Analyses were conducted concerning the accumulation of four metals representing the group of macroelements, i.e. sodium, potassium, calcium and magnesium in two ponds located in the city of Słupsk. Water samples for chemical analyses were collected from the surface microlayer using a Garrett net. At the same time subsurface water samples were collected. Concentrations of metals were determined using a mass spectrometer. Generally, amounts of sodium, potassium, calcium and magnesium were similar in surface microlayer and subsurface water. Only in the case of potassium and calcium was low enrichment observed in the surface microlayer in one pond, while the greatest extent for magnesium enrichment was observed in the spring period.
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38

Johri, Parul, Mala Trivedi, and Sujeet Pratap Singh. "Atom based Profiling and Functional Enrichment analysis of Aquaporins." Research Journal of Biotechnology 16, no. 10 (September 25, 2021): 75–77. http://dx.doi.org/10.25303/1610rjbt7577.

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Sequence analysis is a computational biology method to study protein sequences by comparing amino acids of one protein sequence with the other (residual level comparison). This study reveals a new concept of comparing protein sequences at their basic atomic level. Aquaporins from various origin were compared at their atomic level and the study revealed that all the aquaporin proteins have a closed range of 31.0% to 34.2% of carbon atoms irrespective of their origin and amino acid sequence. Further the protein interaction and functional enrichment analysis of AQP7 showed significant interaction with glycerol kinase and ATP-sensitive inward rectifier potassium channel protein. Our insilico analysis on aquaporin proteins exposed that nature tends to maintain the overall carbon atom composition in the proteins regardless of their amino acid sequence composition which could be further used for their classification. Also, the most highly interacting partners for AQPs are the potassium buffering channel proteins.
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39

Lanzerstorfer, Christof. "Combustion of Miscanthus: Composition of the Ash by Particle Size." Energies 12, no. 1 (January 7, 2019): 178. http://dx.doi.org/10.3390/en12010178.

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Miscanthus is an energy crop considered to show potential for a substantial contribution to sustainable energy production. In miscanthus combustion, 2.0% to 3.5% of the mass of the fuel remains as ash. This ash is less contaminated by heavy metals than ash from wood combustion. The concentrations are well below the typical limit concentrations for use as a soil conditioner on agricultural land and forests. The potassium concentration in the investigated miscanthus ash of 14.1% K2O was significantly higher than the typical concentration of potassium in ashes from wood combustion (3% to 7% K2O). However, in comparison to wood ashes, only very little enrichment of potassium in the fine size fractions of miscanthus ash was found. For most of the other elements, the enrichment in the fine size fractions was also low. Therefore, the production of a potassium-rich material by classification for the production of potassium fertilizer is not feasible. The absence of such an enrichment can be explained on the one hand by the significantly lower combustion temperature in the miscanthus combustion plant and, on the other hand, by the higher molar ratio of K to Cl and the low ratio of K to Si. Thus, the most sensible utilization of miscanthus ash is its direct recycling to the soil such as where the miscanthus plants are grown.
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40

Assylkhankyzy, A., G. Seitmagzimova, and I. Petropavlovsky. "OPTIMIZATION OF THE ENRICHMENT PROCESS OF CHELKAR DEPOSIT POTASSIUM ORE." Herald of Kazakh-British technical university 18, no. 3 (September 1, 2021): 13–21. http://dx.doi.org/10.55452/1998-6688-2021-18-3-13-21.

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В статье рассмотрены результаты исследования процесса переработки отмытой ка- лийной руды месторождения Челкар с целью получения безбалластного калийного удобрения. Изучена эффективность двух- и трехкратной отмывки руды от солей натрия для определения оптимально- го режима обогащения руды по калию. Установлено, что целесообразно проводить двукратную от- мывку руды промывной водой, при которой обеспечивается максимальное содержание в руде калия и минимальное содержание солей натрия. Эффективность отмывки подтверждается результатами рентгенографического анализа руды после второй отмывки. Прокалка руды приводит к дегидрата- ции кристаллогидратов минералов и возрастанию содержания в ее составе основных компонентов. Растворение прокаленной руды при температурах 50 и 90°С приводит лишь к частичному переходу в раствор солей калия и магния при полном растворении остаточного количества солей натрия. Для достижения полного растворения сульфатов калия и магния, являющихся целевыми компонентами для получения минерального удобрения, требуется изучить химические методы превращения.
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41

Zemek, Josef, and Ondrej Gedeon. "Potassium surface enrichment in mixed alkali glass irradiated with electrons." Journal of Non-Crystalline Solids 337, no. 3 (July 2004): 268–71. http://dx.doi.org/10.1016/j.jnoncrysol.2004.04.025.

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42

Dikhtievskaya, L. V., L. F. Shlomina, E. O. Osipova, V. V. Shevchuk, and F. F. Mozheyko. "Flotation enrichment of potash ores of different mineralogical composition." Proceedings of the National Academy of Sciences of Belarus, Chemical Series 55, no. 3 (September 13, 2019): 277–87. http://dx.doi.org/10.29235/1561-8331-2019-55-3-277-287.

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The studies on the development of flotation enrichment technology for potash ores (sylvinite, kainit-halite, carnallite-kainit-halite) were conducted. Optimal flotation conditions: salt composition, density and pH of the dispersion medium, collector of the useful component, auxiliary reagents-frothers, hydrophobisators, depressors for obtaining highly enriched potassium-containing concentrate have been developed for each ore. On the example of sylvinite ore enriched by direct flotation in ore-saturated solutions with a density of 1235 kg/m3, it was shown that the use of a combination of frothers (pine oil, polyethylene glycol) and apolar reagents (liquid paraffins, industrial oil) as part of a complex collector based on higher aliphatic amines (C16 –C18) provides an increase in the extraction of potassium chloride to the concentrate with high quality of the latter. For kainite-halite ore enriched by direct flotation in the saturated aqueous solution of magnesium chloride with a density of 1284 kg/m3 and pH 6–7, lower aliphatic amines (C10 –C12) in combination with amyl alcohol or caprylic acid are effective as a collector of kainite. Carnallite-kainite-halite ore is enriched by reverse flotation in aqueous solutions of magnesium chloride with a density of 1285–1295 kg/m 3 and pH 3–4 using the halite collector of the hydrochloric acid salt of alkylmorpholine.
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43

Sorette, MP, K. Shiffer, and MR Clark. "Improved isolation of normal human reticulocytes via exploitation of chloride-dependent potassium transport." Blood 80, no. 1 (July 1, 1992): 249–54. http://dx.doi.org/10.1182/blood.v80.1.249.249.

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Abstract Studies on normal human reticulocytes have been limited by a lack of methods for effective reticulocyte enrichment. This study shows a convenient new approach for selective enrichment of reticulocytes from normal blood samples. We have developed a modified arabinogalactan density gradient that contains high potassium levels, approximating the internal cation composition of red blood cells (RBC). The low-density populations from this gradient are enriched in reticulocytes, and the highly selected lowest density fraction shows a much higher reticulocyte enrichment than that obtained with high sodium chloride arabinogalactan density gradients, or other previously reported density gradient methods. We found that this improved isolation is caused by suppression of potassium loss and reticulocyte dehydration via chloride (KCI) cotransport. When the low-density fraction of RBC from a high- potassium gradient was subsequently incubated in high sodium chloride medium and reseparated on a sodium chloride density gradient, the reticulocytes dehydrated and were recovered in high-density fractions. The highest-density fractions from this secondary gradient yield 95% to 99% reticulocytes. We anticipate that this method will benefit investigators who require reticulocyte enriched populations for a wide variety of applications.
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44

Sorette, MP, K. Shiffer, and MR Clark. "Improved isolation of normal human reticulocytes via exploitation of chloride-dependent potassium transport." Blood 80, no. 1 (July 1, 1992): 249–54. http://dx.doi.org/10.1182/blood.v80.1.249.bloodjournal801249.

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Studies on normal human reticulocytes have been limited by a lack of methods for effective reticulocyte enrichment. This study shows a convenient new approach for selective enrichment of reticulocytes from normal blood samples. We have developed a modified arabinogalactan density gradient that contains high potassium levels, approximating the internal cation composition of red blood cells (RBC). The low-density populations from this gradient are enriched in reticulocytes, and the highly selected lowest density fraction shows a much higher reticulocyte enrichment than that obtained with high sodium chloride arabinogalactan density gradients, or other previously reported density gradient methods. We found that this improved isolation is caused by suppression of potassium loss and reticulocyte dehydration via chloride (KCI) cotransport. When the low-density fraction of RBC from a high- potassium gradient was subsequently incubated in high sodium chloride medium and reseparated on a sodium chloride density gradient, the reticulocytes dehydrated and were recovered in high-density fractions. The highest-density fractions from this secondary gradient yield 95% to 99% reticulocytes. We anticipate that this method will benefit investigators who require reticulocyte enriched populations for a wide variety of applications.
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45

Askarova, Gulzhan, Mels Shautenov, and Kulzhamal Nogaeva. "Flotation enrichment of resistant gold ores." E3S Web of Conferences 168 (2020): 00005. http://dx.doi.org/10.1051/e3sconf/202016800005.

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Ores of the Vasilkovsky deposit include arsenopyrite, pyrite, pyrrhotite, marcasite, gold, chalcopyrite, sphalerite, galena, faded ore (tennantite)S, bismuthine, native bismuth, lellingite, molybdenite, cubanite, bornite, antimonite, relict minerals, magnetite, apatite and apatite chromite, sericite, chlorite, potassium feldspar, tourmaline), quartz, carbonates (siderite, ankerite, calcite), fluorite, barite. Arsenopyrite is the main ore mineral. It contains the bulk of gold, as well as impurities - copper, cobalt, nickel, bismuth, zirconium, titanium, lead, zinc, antimony, silver, molybdenum. Bismuth and its minerals are widespread, they are constantly associated with arsenopyrite, forming intergrowths with native gold, less often with chalcopyrite and faded ore. Native gold is distributed very unevenly, forms the finest precipitates ranging in size from tenths of a micron to 0.063 mm, grows together with quartz, arsenopyrite, pyrite and bismuth minerals. Rich ores were formed by combining bismuthcontaining associations with arsenopyrite. The role of gold in arsenopyrite increases with depth. Ores are of the gold-quartz-sulfide type. Quartz in ore up to 90 %, sulfides from 3 to 5 %. The content of harmful impurities (arsenic) reaches 2 % or more. Ores are refractory, require special technology for the beneficiation and extraction of gold.
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46

Wen, Xinrong, and Changqing Tu. "Separation/enrichment of Nickel(II) using Potassium Bromide-PAN-Phenolphthalein System." IOP Conference Series: Earth and Environmental Science 647 (January 27, 2021): 012089. http://dx.doi.org/10.1088/1755-1315/647/1/012089.

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47

Tu, Changqing, and Xinrong Wen. "Separation/enrichment of trace Zinc using potassium bromide-dimethylglyoxime-thymolphthalein system." IOP Conference Series: Earth and Environmental Science 121 (February 2018): 022007. http://dx.doi.org/10.1088/1755-1315/121/2/022007.

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48

Markiewicz-Żukowska, Renata, Anna Puścion-Jakubik, Monika Grabia, Jakub Perkowski, Patryk Nowakowski, Joanna Bielecka, Jolanta Soroczyńska, Grzegorz Kańgowski, Jakub M. Bołtryk, and Katarzyna Socha. "Nuts as a Dietary Enrichment with Selected Minerals—Content Assessment Supported by Chemometric Analysis." Foods 11, no. 20 (October 11, 2022): 3152. http://dx.doi.org/10.3390/foods11203152.

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Nuts used as a snack and meal accompaniment supply plant protein and fatty acids that are beneficial for human health; however, they can also provide minerals. The aim of this study was to determine the content of selected elements that are often deficient in the diet (calcium, potassium, magnesium, selenium, and zinc) in nuts and determine whether they can be used to supplement deficiencies in the diet. In this study, we analyzed 10 types of nuts (n = 120 samples) that are consumed and available for sale in Poland. The content of calcium, magnesium, selenium, and zinc was determined by the atomic absorption spectrometry method, and flame atomic emission spectrometry was used for determination of potassium contents. The highest median calcium content was found in almonds (2825.8 mg/kg), the highest potassium content in pistachio nuts (15,730.5 mg/kg), the highest magnesium and selenium contents in Brazil nuts (10,509.2 mg/kg and 4348.7 μg/kg, respectively), and the highest zinc content in pine nuts (72.4 mg/kg). All the tested nuts are a source of magnesium, eight types of tested nuts are a source of potassium, six nut types are a source of zinc, and four nut types are a source of selenium; however, among the tested nuts, only almonds can be considered a source of calcium. Moreover, we found that selected chemometric methods can be useful in the classification of nuts. The studied nuts are valuable products that can be used to supplement the diet with selected minerals and can therefore be labelled as functional products crucial for disease prevention.
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49

KWAGA, JACOB, JOHN O. IVERSEN, and JAMES R. SAUNDERS. "Comparison of Two Enrichment Protocols for the Detection of Yersinia in Slaughtered Pigs and Pork Products." Journal of Food Protection 53, no. 12 (December 1, 1990): 1047–49. http://dx.doi.org/10.4315/0362-028x-53.12.1047.

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Two enrichment methods were evaluated in the course of a study to determine the occurrence of Yersinia enterocolitica in slaughtered pigs and pork products. Eighty Yersinia strains belonging to one of four species were recovered. Of the 67 strains of Y. enterocolitica encountered, 48 belonged to known pathogenic bioserotypes. The enrichment medium incorporating irgasan, ticarcillin, and potassium chlorate (ITC) was found to be superior to the two-step enrichment method (YER/BOS) for isolation of pathogenic Y. enterocolitica from throat swabs. When pork products were examined using the two methods, YER/BOS was by far superior for recovery of yersiniae, although all strains isolated by this method belonged to nonpathogenic bioserotypes and Y. enterocolitica-like organisms. Conversely, ITC enrichment recovered fewer strains but most were pathogenic bioserotypes. Thus, swine can serve as a reservoir of virulent Y. enterocolitica in Saskatchewan, and ITC enrichment is recommended for the isolation of these strains.
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Stergiou, Christos L., Vasilios Melfos, Panagiotis Voudouris, Lambrini Papadopoulou, Paul G. Spry, Irena Peytcheva, Dimitrina Dimitrova, Elitsa Stefanova, and Katerina Giouri. "Rare and Critical Metals in Pyrite, Chalcopyrite, Magnetite, and Titanite from the Vathi Porphyry Cu-Au±Mo Deposit, Northern Greece." Minerals 11, no. 6 (June 14, 2021): 630. http://dx.doi.org/10.3390/min11060630.

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The Vathi porphyry Cu-Au±Mo deposit is located in the Kilkis ore district, northern Greece. Hydrothermally altered and mineralized samples of latite and quartz monzonite are enriched with numerous rare and critical metals. The present study focuses on the bulk geochemistry and the mineral chemistry of pyrite, chalcopyrite, magnetite, and titanite. Pyrite and chalcopyrite are the most abundant ore minerals at Vathi and are related to potassic, propylitic, and sericitic hydrothermal alterations (A- and D-veins), as well as to the late-stage epithermal overprint (E-veins). Magnetite and titanite are found mainly in M-type veins and as disseminations in the potassic-calcic alteration of quartz monzonite. Disseminated magnetite is also present in the potassic alteration in latite, which is overprinted by sericitic alteration. Scanning electron microscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of pyrite and chalcopyrite reveal the presence of pyrrhotite, galena, and Bi-telluride inclusions in pyrite and enrichments of Ag, Co, Sb, Se, and Ti. Chalcopyrite hosts bornite, sphalerite, galena, and Bi-sulfosalt inclusions and is enriched with Ag, In, and Ti. Inclusions of wittichenite, tetradymite, and cuprobismutite reflect enrichments of Te and Bi in the mineralizing fluids. Native gold is related to A- and D-type veins and is found as nano-inclusions in pyrite. Titanite inclusions characterize magnetite, whereas titanite is a major host of Ce, Gd, La, Nd, Sm, Th, and W.
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