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Journal articles on the topic 'Silver deposits'

Author: Grafiati

Published: 4 June 2021

Last updated: 8 February 2022

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1

Novoselov, Konstantin, Elena Belogub, Ekaterina Palenova, and Ivan Blinov. "Silver minerals in the Unkur sandstone-hosted Cu deposit (Transbaikalia region, Russia)." Neues Jahrbuch für Mineralogie - Abhandlungen Journal of Mineralogy and Geochemistry 196, no. 3 (July 1, 2020): 221–30. http://dx.doi.org/10.1127/njma/2020/0192.

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The Kodar-Udokan ore district in the Transbaikalia region of Russia contains numerous sandstone-hosted Cu deposits and occurrences with variable Ag content. The Unkur deposit with possible resources of 62 million tonnes at 0.53 % Cu and 38.6 g/t Ag is hosted in metasedimentary rocks of the Udokan Group of 2.2–2.6 Ga in age. The bornite–chalcopyrite ores from the deposit are characterized by disseminated, lenticular, pocket, and veinlet textures and also contain numerous silver minerals including native silver, mercurian silver (up to 37.4 wt% Hg), stromeyerite, mckinstryite, balkanite, and naumannite. Isomorphic silver is also hosted in bornite (up to 3.8 wt%) and chalcocite (up to 1.8 wt% Ag). The microscopic relationships between ore minerals and stability of stromeyerite indicate almost synchronous formation of native silver, mercurian silver, and stromeyerite at a temperature of < 100 °C. The presence of Ag–Hg minerals is a characteristic feature of ores from the Cu–Ag deposits hosted in sedimentary and carbonate-sedimentary rocks.

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2

Hirata, A., P. Baluk, T. Fujiwara, and D. M. McDonald. "Location of focal silver staining at endothelial gaps in inflamed venules examined by scanning electron microscopy." American Journal of Physiology-Lung Cellular and Molecular Physiology 269, no. 3 (September 1, 1995): L403—L418. http://dx.doi.org/10.1152/ajplung.1995.269.3.l403.

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The century-old histological technique of silver nitrate staining has proven to be extremely useful for visualizing endothelial cell borders and localizing endothelial gaps, but the significance of the staining is still not fully understood. To gain some insight into what silver nitrate stains, we developed a method that enabled us to use scanning electron microscopy with backscattered and secondary electron imaging to examine silver staining at endothelial cell borders of venules of the rat tracheal mucosa. We found that in normal venules, silver lines followed the smooth contour of cell borders. However, 1 min after endothelial permeability was increased by substance P, cell borders were irregular and displaced from the silver lines by as much as 4.3 microns, and the lines were accompanied by three types of silver deposits. Most common (46% of total) were annulus-shaped silver deposits that surrounded endothelial gaps. These deposits averaged 1.5 microns in width, were positioned symmetrically across cell borders, and were located at a depth of 0.3 micron beneath the luminal surface. Many endothelial gaps were partitioned into multiple pores (mean, 2.4) by fingerlike processes of endothelial cells. Surprisingly, the gaps occupied only 5.4% of the total area of the silver deposits and constituted 0.15% of the luminal surface of the leaky postcapillary venules. A second type of silver deposit (19% of total) was positioned asymmetrically with respect to the cell border and marked sites where endothelial cell margins still overlapped but appeared to be vertically separated by obliquely oriented gaps. A third type marked gaps at three-cell junctions; these were no more abundant than deposits elsewhere around the cell perimeter, suggesting that three-cell junctions were not unusually leaky sites. We conclude that silver nitrate marks endothelial cell borders and outlines endothelial cell gaps by staining an element of intercellular junctions. The annular shape of many silver deposits around gaps suggests that junctional elements in the apposing cells are separated during gap formation but are still present at the gap perimeter.

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3

De la Nuez Colon, D., and M. Santa Cruz Pacheco. "Gold and gold-bearing volcanogenic massive sulphide deposits of the Central Cuba." Proceedings of higher educational establishments. Geology and Exploration, no. 3 (February 28, 2021): 27–37. http://dx.doi.org/10.32454/0016-7762-2020-63-3-27-37.

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Background. Volcanogenic massive sulphide deposits (VMS) are the most important sources of Cu and Zn; they account for a large share of the world production of Pb, Ag, Au, Se, Te, Bi and Sb, as well as small amounts of many other metals. The polymetallic VMS deposits of economic value of varying degrees are known in the rocks of the Los Pasos Cretaceous Formation, Cuba.Aim. To show the potential of the Cretaceous volcanic deposits of Central Cuba for gold, silver, copper, zinc and lead deposit prospecting.Materials and methods. The study characterises the San Fernando, Independencia, Antonio, Los Cerros VMS deposits and the Boca del Toro and El Sol ore occurrences located in the Los Pasos Formation. The similarities and differences in the mineral and elemental composition and structures of the ores of these objects are described, which underlie the assessment of their economic importance.Results. The latitudinal zoning of VMS and noble metal mineralisation of the Central Cuban ore region is outlined. In the west, copper-VMS deposits with accompanying gold ore objects prevail. In the east, copper-zinc VMS deposits with barite and gold-silver objects are widespread.Conclusions. It is necessary to assume the different erosional sections corresponding to the blocks of the Cretaceous volcanic arc of Central Cuba, which is larger in the west and smaller in the east. Proceeding from the presence of veinlet gold ores, their confinement to tectonic zones and the lack of correlation between noble and chalcophile metals at the San Fernando deposit, as well as significantly different gold-silver ratios in the considered ore objects, it could be assumed that some of the gold-silver ores were formed after VMS. The obtained Au/Ag ratios are close to the ores of the high sulphidation type (high sulphide ores) from similar ore regions of Venezuela and the Kur-il island arc. In this regard, one can expect hidden gold deposits in the west and gold-silver deposits in the east of the studied area.

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4

THALHEIM, KLAUS. "THE 1477 SILVER FIND AT THE ST. GEORG MINE IN SCHNEEBERG AND SIGNIFICANT ORE SPECIMENS IN THE MUSEUM OF MINERALOGY AND GEOLOGY IN DRESDEN." Earth Sciences History 38, no. 2 (November 1, 2019): 157–72. http://dx.doi.org/10.17704/1944-6178-38.2.157.

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ABSTRACT Two silver ore specimens in the mineralogical collection of the Senckenberg Natural History Collections Dresden, Museum of Mineralogy and Geology, are samples from one of the most spectacular silver finds in Saxon Erzgebirge. The history of the find and of the two silver ore specimens is discussed. The origin of such a rich deposit of silver ore is examined in relationship to the geology of mineral deposits.

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5

Goldsmith, L. B., A. J. Sinclair, and P. B. Read. "Exploration implications of production and location data for Ag-rich vein deposits, Trout Lake mining camp, southeastern B.C." Canadian Journal of Earth Sciences 23, no. 10 (October 1, 1986): 1627–40. http://dx.doi.org/10.1139/e86-152.

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Ore tonnage production data from 43 former producers in the Trout Lake mining camp are examined using plots of spatial density of deposits and statistical methods. Outlines of mineral belts are established from spatial density with the 0.5 deposit per 4 km2 contour. Probability plots of ore tonnages distinguish two lognormal populations of deposits. Probablity plots of metal grades show four lognormal populations of silver and two of gold. A metal content versus ore tonnage graph draws attention to the similarity in proportions of metals produced from high-tonnage and from medium- + low-tonnage deposits. Triangular graphs of metal contents emphasize the direct relationship between silver and lead; metal ratios suggest some relationships that may be dependent upon host rocks. Linear correlation coefficients of tonnage and metal content show an inverse relationship between tonnage and precious metals and a direct relationship between silver and lead. Multiple regression models established between production tonnages and average grades can estimate deposit size within one order of magnitude.Systematic evaluation of quantitative production and location data can augment exploration decisions.

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6

Abriou, D., D. Gagnot, J. Jupille, and F. Creuzet. "Morphology of Silver Thin Films Deposited on TiO2(110) Surfaces." Surface Review and Letters 05, no. 01 (February 1998): 387–92. http://dx.doi.org/10.1142/s0218625x98000712.

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The growth mode of silver films deposited at room temperature on TiO 2(110) surfaces has been examined by means of atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) in ultrahigh vacuum (UHV) conditions, On clean vacancy-free TiO 2(110) surfaces, 0.1-nm-thick (on average) Ag deposits form a two-dimensional (2D) layer. When the thickness of the silver overlayer is increased, 3D clusters are shown to appear while the 2D film is preserved, furthermore, the influence of surface oxygen vacancies on the growth of Ag/TiO 2(110) is evidenced by well-characterized differences in the morphology of 9-nm-thick silver deposits.

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7

P Marshall, Craig, Karen L Mackenzie, Junhong Chen, Dorothy Z Oehler, Graham A Logan, and Malcolm R Walter. "Microbes, organic matter and ore deposits." Microbiology Australia 25, no. 1 (2004): 36. http://dx.doi.org/10.1071/ma04136.

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The 1640 Ma (million years old) Here?s Your Chance (HYC) deposit at McArthur River, Northern Territory, Australia is one of the largest and least metamorphosed lead-zinc-silver deposits in the world. The mineralised interval has been divided into several orebodies and is separated by relatively barren sediment.

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8

PATERSON, COLIN J. "Ore Deposits of Gold and Silver." Mineral Processing and Extractive Metallurgy Review 6, no. 1-4 (January 1990): 43–66. http://dx.doi.org/10.1080/08827509008952656.

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9

Pak, S. J., S. G. Choi, and S. H. Choi. "Systematic mineralogy and chemistry of gold-silver vein deposits in the Taebaeksan district, Korea: Distal relatives of a porphyry system." Mineralogical Magazine 68, no. 3 (June 2004): 467–87. http://dx.doi.org/10.1180/0026461046830199.

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AbstractGold-silver vein deposits in the Taebaeksan district, Korea, coexist in time and space with a variety of other deposit types such as skarns, hydrothermal carbonate replacement bodies and Carlin-like deposits and reflect proximity to a magmatic source. The seven gold-silver deposits within the district show common features such as multiple complex veins, an abundance (up to 30% in ore) of base-metal sulphides, a wide range of Ag/Au ratios and the common occurrence of carbonate. Quartz-vein textures indicate open-space-filling at shallow crustal levels. On the basis of Ag/Au ratios of ore, mode of occurrence, and associated mineral assemblages, the seven deposits studied can be classified as follows; Au-dominant type (Group I), Au-Ag type (Group II), Ag-dominant type (Group IIIA) and base-metal and Ag-dominant type (Group IIIB). Group I is characterized by paragenetically early Pb-Zn basemetal sulphides with electrum and late, rare Ag-sulphides and Ag-sulphosalts, whereas Group III contains more Ag-sulphides and/or Ag-sulphosalts. Group II is gold-rich, but transitional to Group III. The Au contents and FeS contents of electrum and sphalerite, respectively, from all of the deposits decreased as mineralization proceeded. Temperature and log fS2 conditions of gold-silver mineralization tend to decrease from Group I and II to Group III deposits (i.e. 340–270°C, –9.3 to –11.8 bar, 320–240°C, –9.5 to –10.3 bar, 250–160°C, –12.5 to –16.9 bar, respectively) as well as from the main to late stages of mineralization in each deposit. The systematic mineralogy and variation of physicochemical conditions in Groups I, II and III are thought to be due to their relative positions with respect to a magma source that is genetically related to a low-to-intermediate-sulphidation porphyry system. Au-rich deposits are proximal to a magmatic source, whereas Ag-rich deposits are more distal.

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10

Smyk, Mark C., and James M. Franklin. "A synopsis of mineral deposits in the Archean and Proterozoic rocks of the Lake Nipigon Region, Thunder Bay District, Ontario." Canadian Journal of Earth Sciences 44, no. 8 (August 1, 2007): 1041–53. http://dx.doi.org/10.1139/e07-013.

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A variety of metallic and non-metallic mineral deposit types occur within Archean and Proterozoic rocks in the area encompassing the Lake Nipigon Region Geoscience Initiative. Archean deposit types include Algoma-type banded iron formation-hosted iron (e.g., Lake Nipigon iron range); volcanogenic massive sulphide copper–zinc (e.g., Onaman–Tashota belt); ultramafic intrusion-hosted chromium (e.g., Puddy–Chrome lakes); mafic to ultramafic intrusion-hosted copper–nickel – platinum group element (PGE) (e.g., Lac des Iles); and pegmatite-hosted deposits of rare metals (Li, Ta, Be), uranium, and molybdenum (e.g., Georgia Lake field, Black Sturgeon Lake, and Anderson Lake, respectively). Mesothermal lode gold deposits are prominent in the Beardmore–Geraldton camp. Superior-type iron formation occurs in Paleoproterozoic Gunflint Formation. "Red-bed" copper occurs in Mesoproterozoic Midcontinent Rift-related Osler Group volcanic and interflow sedimentary rocks. Native copper and copper sulphides occur in Mesoproterozoic Sibley Group sedimentary rocks, adjacent to ultramafic intrusions. These mafic to ultramafic intrusions, associated with Midcontinent Rift magmatism, host copper–nickel–PGE deposits (e.g., Seagull, Great Lakes Nickel). Silver-bearing veins occur in Paleoproterozoic Animikie Group sedimentary rocks in proximity to Midcontinent Rift-related mafic intrusions (e.g., Silver Islet, Silver Mountain). Lead–zinc–barite veins, uranium-bearing veins, and amethyst vein and replacement-type deposits may be cogenetic and formed at or near the unconformity between Sibley Group basal sandstone and underlying Archean granitic basement (e.g., Dorion, Black Sturgeon Lake, McTavish Township). The hydrothermal systems that produced all of these veins were probably driven by heat associated with Midcontinent rifting. Many occur in structures related to rift-bounding faults. Iron oxide – copper–gold deposits may occur near the English Bay intrusion.

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11

Shevelev, G. A., L. I. Vasilenko, E. N. Kamenskaya, T. S. Turmagambetov, N. G. Kamensky, A. A. Poyaurel, and K. Dzh Aibekov. "Noble and Rare Metals in Some Coal Deposits of Kazakhstan." Industrial laboratory. Diagnostics of materials 85, no. 1II) (February 15, 2019): 38–44. http://dx.doi.org/10.26896/1028-6861-2019-85-1-ii-38-44.

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The concentrations of the impurities in brown coals some of Kazakhstan deposits — «Kulan», «Shoptikol’», «Oi Karogai», «Sarykum» — were determined. Surface inclusions in coals were studied using optical USB microscopes. The composition of inclusions and total composition of coals were analyzed by both X-ray spectrometry with energy dispersion and atomic emission spectrometry using «Grand-Potok» complex with sample introduction by the spill-injection method into an arc discharge and recording spectra with an analyzer MAÉS. Gold was determined on a «Grand-Potok» complex using scintillation method. The coals of «Oi Karogai», «Sarykum», and «Kulan» deposits exhibited inclusions of pyrite in crystalline form. It was shown, that both gold and silver are present only in the coals of the «Shoptikol’» deposit in the form of flat round inclusions. Inclusions formed particles of gold-silver alloy upon melting according to data of scintillation analysis. The average concentrations of gold and silver in the coal samples of the «Shoptikol’» deposit are 0.007 and 0.03 ppm, respectively. It is shown that scintillation determination of precious metals in brown coals of Kazakhstan on a «Grand-Potok» complex with MAÉS analyzer is more rapid compared to the methods of inductively-coupled plasma-mass spectrometry (ICP-MS), atomic emission spectrometry (AES) and atomic absorption spectrometry (AAS) at comparable detection limits.

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12

Tong, Jing Gui, Yu Tong Yan, and Na Zhang. "Chemical Composition Characteristics of Calcite in Gold and Silver Deposits in Jiaodong Peninsula, China." Advanced Materials Research 960-961 (June 2014): 18–21. http://dx.doi.org/10.4028/www.scientific.net/amr.960-961.18.

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The largest gold district in China is the Jiaodong Peninsula. This study is based on chemical composition characteristics of calcite from gold deposits in Jiaodong. In this paper, a new formula was proposed to character the chemical composition characteristics of calcite in gold and silver deposits. The results showed that the chemical composition characteristics of calcite between gold and silver deposits were of great difference. And each data focused in each area. The spots of gold deposits located in the area of riched CO2 areas. But the spots of silver deposits located in the area of riched CaO areas. The reason of these differences was mainly resulted from each different ore-forming condition.

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13

Lavrik, Natalya, Natalya Litvinova, Tatyana Aleksandrova, Valentina Stepanova, and Alexandra Lavrik. "Platinum mineralization comparative characteristics of the some Far East deposits." E3S Web of Conferences 56 (2018): 04017. http://dx.doi.org/10.1051/e3sconf/20185604017.

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In this article shown platinum mineralization comparative characteristics for three deposits: Kondoer-traditional unique deposit and other two probably alternative source of platinum: the Poperechnoe ironmanganese deposit and the Malmyzh copper-porphyry deposit. Platinoids of the Kondoer deposit are the chain Pt>>Ir>Os>Ru=Rh>Pd. The presences of platinum crystals are characteristic, there are over 50 rare and new platinoids minerals in different combinations. There are gold and silver. Platinoids from the iron-manganese ore of Poperechnoe are as Pt>>Rh≈Ir>Ru≈Os>Pd. A scattered dissemination of arsenide sulfate and sulfides of Rh, Ir, Ru, Os are noted in the platinum. Palladium is present as impurities in gold and platinum. The gold content is different-with admixtures Ag, Pb, Cd, Fe. At this stage the platinoids content in oxidized ores of the Malmyzh gold-copper porphyry deposit is Pt ≈ Pd. The gold is present as electrum. There is native silver cadmium.

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14

MELNIKOV, ANTON VLADIMIROVICH, VITALY ALEKSEEVICH STEPANOV, and DMITRIY VALERYEVICH YUSUPOV. "DISCOVERY AND STUDY HISTORY POKROVSKY GOLD ORE DEPOSIT IN THE AMUR REGION." Messenger AmSU, no. 91 (2020): 63–72. http://dx.doi.org/10.22250/jasu.11.

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A brief history of the discovery and study of the large Pokrovsky gold ore deposit of the Amur Region, from the ores of which about 63 tons of gold were extracted, is given. The role of scientific and production organizations and individual geologists in the discovery of the deposit is shown. According to the results of almost half a century of research, the deposit is classified as a near-surface gold-silver formation with a typical composition of ores, near-ore metasomatites and native gold for deposits of this type. The closest analogue of Pokrovka is the Kubak deposit of the Omolonsky gold-silver province.

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15

SHI, ZHONG-TAO, MIN HAN, SHI-FENG ZHAO, LU ZHANG, XUE-FEI LI, JIAN-GUO WAN, and GUANG-HOU WANG. "SELF-ASSEMBLY OF SILVER NANOCLUSTERS ON TRIBLOCK COPOLYMER TEMPLATES." International Journal of Modern Physics B 19, no. 15n17 (July 10, 2005): 2792–97. http://dx.doi.org/10.1142/s0217979205031717.

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Poly (styrene-b-butadiene-b-styrene) (SBS) triblock copolymer templates have been prepared by solvent-induced order-disorder phase transition method. Silver nanoclusters have been deposited onto the SBS copolymer templates by low energy clusters beam deposition (LECBD) method. The microstructures of the template and cluster deposits have been characterized by AFM with tapping-mode. It is shown that the triblock copolymers are self-assembled to form an in-plane cylinder ordered microstructure. In the case of low coverage (<50%), silver nanaoclusters deposited on the template tend to aggregate along with the pattern of the template and coalesce into larger nanoparticles. Optical absorption spectra reveal that the surface plasmon resonance (SPR) of silver nanoclusters deposited on the template occurs at 545nm, being a red shift of ~75nm compared to that silver nanoclusters deposited on the fused quartz substrate.

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16

MOISEENKO, NATALIA VALENTINOVNA, and SVETLANA MIKHAILOVNA AVRAMENKO. "SILVER IN THE GOLD DEPOSITS OF THE AMUR REGION." Messenger AmSU, no. 93 (2021): 130–36. http://dx.doi.org/10.22250/jasu.93.27.

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The main minerals of native silver hubs on gold deposits of the Amur region (Albyn, Malomyr, Pioner, Pokrovskoe) were studied. It has been established that silver has a positive correlation with gold, zinc, arsenic, antimony, lead and cadmium. There is a negative correlation of silver with zirconium, yttrium, hafnia, tantalum and rare earth elements.

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17

Kuntyi, O., G. Zozulya, I. Saldan, V. Kree, S. Korniy, and B. Stel’makhovych. "Nature of the silver precipitation obtained by cementation from thiosulphate solutions." Open Chemistry 9, no. 1 (February 1, 2011): 180–84. http://dx.doi.org/10.2478/s11532-010-0139-3.

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AbstractThe morphology and composition of the deposits formed on the surface of magnesium disk during cementation from thiosulphate solutions (0.0025–0.1M) [Ag(S2O3)2]3− + 0.5M S2O3 2− have been studied. A porous deposit with low adhesion is formed on the surface of the magnesium metal substrate. Within a wide range of [Ag(S2O3)2]3− ion concentrations, sulfur as well as silver are constituents of the deposit at the initial stages of cementation and at the end of the reaction. This is attributed to the electrochemical behaviour of magnesium in thiosulphate solutions resulting in the exceeding of current limit on cathode for pure silver reduction. Hence, parallel electrochemical reactions take place that are very close in their values to the standard redox potentials of reduction of [Ag(S2O3)2]3− ions to Ag0 and S2O32− ions to S2−. Sulfur content in the cement deposits increases with the decrease in [Ag(S2O3)2]3− ion concentration and increase in cementation time. This tendency is also observed with the decreasing solution temperature.

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18

Stepanov, V. A. "Reference couple gold deposit — placer as a basis for forecasting of the new gold deposits in Amur river basin." Proceedings of higher educational establishments. Geology and Exploration, no. 6 (January 3, 2019): 49–58. http://dx.doi.org/10.32454/0016-7762-2018-6-49-58.

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About 1400 placers and several dozens of ore gold deposits are known in the Amur gold-bearing province. Placers are to a large degree worked out, so the future of the province is seen to be in the discovery of the new gold deposits. The paper shows the dependence of the productivity and composition of the native gold placers on the size and formational affiliation of the placer-forming gold deposit. The reference couples have been identified: the gold deposit and the placer formed due to the erosion of its' upper part. For example, the Tokur gold-quartz deposit is a channel-fill placer in Tokur stream, gold-sulphide-quartz deposit Pioneer—the placer in Ulungi river, gold-sulphide-quartz deposit Bamskoe—the placer of Chulbangro river, Berezitovoye gold-polymetallic deposit—placer of the Konstantinovsky stream and gold-silver field Pokrovskoye—placer of Sergeevsky stream. A forecast of new gold deposits of a certain formation has been made according to the parameters of the placer and the composition of the native gold. A similar selection of reference couples of a gold deposit and a placer with the subsequent forecasting of new deposits can be one of the methods for predicting gold deposits in the other gold-bearing provinces.

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19

Konstantinov, Michael M., Ilia S. Rosenblum, and Sergey F. Strujkov. "Types of epithermal silver deposits, northeastern Russia." Economic Geology 88, no. 7 (November 1, 1993): 1797–809. http://dx.doi.org/10.2113/gsecongeo.88.7.1797.

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20

Volkov, A. V., and A. A. Sidorov. "Economic implications of epithermal gold-silver deposits." Herald of the Russian Academy of Sciences 83, no. 4 (July 2013): 365–74. http://dx.doi.org/10.1134/s1019331613040096.

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21

Cook, Nigel J., Cristiana L. Ciobanu, Paul G. Spry, and Panagiotis Voudouris. "Understanding gold-(silver)-telluride-(selenide) mineral deposits." Episodes 32, no. 4 (December 1, 2009): 249–63. http://dx.doi.org/10.18814/epiiugs/2009/v32i4/002.

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22

Andrews, A. J. "Silver vein deposits: summary of recent research." Canadian Journal of Earth Sciences 23, no. 10 (October 1, 1986): 1460–62. http://dx.doi.org/10.1139/e86-140.

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23

Ridgway, J., B. Martiny, A. Gomez-Caballero, C. Macias-Romo, and M. G. Villasenor-Cabral. "Ammonium geochemistry of some Mexican silver deposits." Journal of Geochemical Exploration 40, no. 1-3 (August 1991): 311–27. http://dx.doi.org/10.1016/0375-6742(91)90045-v.

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24

Plotinskaya, O. Yu. "Mineralogy of precious metals in ores of the Yubileinoe porphyry gold deposit (Kazakhstan)." МИНЕРАЛОГИЯ (MINERALOGY), no. 3 (October 28, 2020): 44–53. http://dx.doi.org/10.35597/2313-545x-2020-6-3-4.

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Gold and silver mineralogy is studied in ores of the Yubileinoe porphyry gold deposit (Kazakhstan). Native gold is the major gold mineral. Its fneness varies from 970‰ in magnetite-hematite assemblage to 733–860‰ in pyrite-chalcopyrite assemblage. Silver occurs as admixture in native gold and, occasionally, as silver telluride. Native gold is associated with bi and Pb minerals: rucklidgeite, galenaclaustalite, and tetradymite-kawazulite. According to chlorite geothermometry, the Au, Ag and bi minerals precipitated at temperatures of 250-230 °С. These features are typical of the porphyry gold deposits worldwide. Figures 5. Tables 3. References 17.

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25

Simmons, Stuart F., and Kevin L. Brown. "Precious Metals in Modern Hydrothermal Solutions and Implications for the Formation of Epithermal Ore Deposits." SEG Discovery, no. 72 (January 1, 2008): 1–12. http://dx.doi.org/10.5382/segnews.2008-72.fea.

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ABSTRACT We determined the concentrations of gold, silver, arsenic, antimony, and mercury in deep hydrothermal solutions (~1 km depth, 200° to >300°C) from active geothermal systems in the Taupo Volcanic Zone, New Zealand, and Ladolam, Lihir Island, Papua New Guinea. The wide range of concentrations in the New Zealand systems and the stable isotope signatures at Ladolam confırm that magmas are an important source of high concentrations of gold and silver in hydrothermal solutions. The Rotokawa geothermal system in New Zealand has the highest hydrothermal fluxes of gold (~30–100 kg/yr) and silver (~5000–11,000 kg/yr), which, if they remained constant, could match the metal inventories of the largest ore deposits in the world in <50,000 years. This relatively short time span is comparable to the amount of time required to account for the known gold resource in ores at Ladolam, which has a slightly lower gold flux (~25 kg/yr). The fact that a giant gold deposit exists at Ladolam, rather than at Rotokawa, demonstrates the importance of fluid focusing and effıcient metal deposition in the formation of epithermal gold and silver ore deposits.

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26

Goodz, M. D., D. H. Watkinson, V. Smejkal, and Z. Pertold. "Sulphur-isotope geochemistry of silver–selpnarsenide vein mineralization, Cobalt, Ontario." Canadian Journal of Earth Sciences 23, no. 10 (October 1, 1986): 1551–67. http://dx.doi.org/10.1139/e86-146.

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The silver–sulpharsenide vein deposits of Cobalt, Ontario, crosscut basement Archean metavolcanic rocks, Proterozoic strata, and younger Proterozoic diabase sills. A petrographic and sulphur-isotope study of the metallic minerals was initiated to assess possible genetic models of vein formation. Discrete differences exist between the sulphur-isotope compositions of basement sulphides (δ34S = + 4.0‰), brecciated wall-rock sulphides (+ 3.5‰), and vein sulphides (+ 2.3‰). The δ34S values consistently increase with distance from the vein centres. Sulphur-isotope fractionation trends are similar for all the vein deposits studied. Sulphur-isotope data suggest that sulphides were deposited between 130 and 254 °C. Based on the assumption of equilibrium between chalcopyrite and galena, the initial δ34S of the fluid was between + 5.0 and + 11.0‰. The release of sulphur during the reaction of Archean pyrite with Proterozoic formational brines to form pyrrhotite is proposed to explain the heavy sulphur isotopic composition of the fluid. This process could also have provided the Ni, Co, and As, known to be concentrated in some pyrite, that was deposited in the silver veins. Interpretation of mineral paragenesis and geothermometry indicate that temperature decreased and aS2 increased as deposition proceeded.

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Berger, Luisa, Katarzyna Madajska, Iwona B. Szymanska, Katja Höflich, Mikhail N. Polyakov, Jakub Jurczyk, Carlos Guerra-Nuñez, and Ivo Utke. "Gas-assisted silver deposition with a focused electron beam." Beilstein Journal of Nanotechnology 9 (January 19, 2018): 224–32. http://dx.doi.org/10.3762/bjnano.9.24.

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Focused electron beam induced deposition (FEBID) is a flexible direct-write method to obtain defined structures with a high lateral resolution. In order to use this technique in application fields such as plasmonics, suitable precursors which allow the deposition of desired materials have to be identified. Well known for its plasmonic properties, silver represents an interesting candidate for FEBID. For this purpose the carboxylate complex silver(I) pentafluoropropionate (AgO2CC2F5) was used for the first time in FEBID and resulted in deposits with high silver content of up to 76 atom %. As verified by TEM investigations, the deposited material is composed of pure silver crystallites in a carbon matrix. It showed good electrical properties and a strong Raman signal enhancement. Interestingly, silver crystal growth presents a strong dependency on electron dose and precursor refreshment.

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28

Rosamilia, J. M., and B. Miller. "Additive enhanced nonaqueous electrodeposition of silver on Ba2YCu3O7." Journal of Materials Research 5, no. 8 (August 1990): 1612–15. http://dx.doi.org/10.1557/jmr.1990.1612.

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A nonaqueous plating bath for silver deposition on the Ba2YCu3O7 superconductor has been modified with thiourea to give enhanced coverage of the metal film at low thicknesses. For both porous and high density ceramic substrates, SEM and optical microscopy show nucleation of silver deposits is increased by the additive. The resulting silver-superconductor contact resistances are comparable to those achieved without additives. Adhesion of the deposits and ease of mechanical handling are improved with thiourea. The combination of highly reactive oxidized substrate, nonaqueous solvent, and strongly surface active agent forms a novel extension for electrodeposition science.

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29

Murashova, I. B., A. P. Khramov, I. V. Zotin, YU P. Zaikov, and V. G. Zyrjanov. "Electrocrystallization of fibrous silver deposits from nitrate melts: Experiments and modeling." Journal of Mining and Metallurgy, Section B: Metallurgy 39, no. 1-2 (2003): 137–47. http://dx.doi.org/10.2298/jmmb0302137m.

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Fibrous silver deposits have been obtained in molten nitrates on a moving cathode. Cylindrical silver cathode was lifted from the melt AgNO3-NaNO3-KNO3. It is found that the dimensions of the silver threads as well as their shape and thickness depend on the electrolysis parameters: the values of current and velocity of the cathode lifting. Systematic study of the silver dendrite structure has been performed on a scanning electron microscope. Geometric characteristics have been evaluated statistically and regression equations linking these constitutive properties of the deposits with the values of current and of lifting velocity have been obtained. A criterion for the description of dendrite shape under different conditions is proposed.

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30

Kahanda, G. L. M. K. S., and Micha Tomkiewicz. "Fractality and Impedance of Electrochemically Grown Silver Deposits." Journal of The Electrochemical Society 137, no. 11 (November 1, 1990): 3423–29. http://dx.doi.org/10.1149/1.2086233.

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31

Than Htun, Aung Kyin, and Khin Zaw. "Chapter 27 Lead–zinc–silver deposits of Myanmar." Geological Society, London, Memoirs 48, no. 1 (2017): 589–623. http://dx.doi.org/10.1144/m48.27.

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32

Culhane, Kyle, Ke Jiang, Aaron Neumann, and Anatoliy O. Pinchuk. "Laser-Fabricated Plasmonic Nanostructures for Surface-Enhanced Raman Spectroscopy of Bacteria Quorum Sensing Molecules." MRS Advances 2, no. 42 (2017): 2287–94. http://dx.doi.org/10.1557/adv.2017.98.

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ABSTRACTA laser deposition technique, based on the photo-reduction of silver ions from an aqueous solution, was used to fabricate silver nanostructure surfaces on glass cover slips. The resulting silver nanostructures exhibited plasmonic properties, which show promise in applications towards surface enhanced Raman spectroscopy (SERS). Using the standard thiophenol, the enhancement factor calculated for the deposits was approximately ∼106, which is comparable to other SERS-active plasmonic nanostructures fabricated through more complex techniques, such as electron beam lithography. The silver nanostructures were then employed in the enhancement of Raman signals from N-butyryl-L-homoserine lactone, a signaling molecule relevant to bacteria quorum sensing. In particular, the work presented herein shows that the laser-deposited plasmonic nanostructures are promising candidates for monitoring concentrations of signaling molecules within biofilms containing quorum sensing bacteria.

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33

Mitkova, Maria I., Michael N. Kozicki, and Janmichael P. Aberouette. "Morphology of electrochemically grown silver deposits on silver-saturated Ge–Se thin films." Journal of Non-Crystalline Solids 326-327 (October 2003): 425–29. http://dx.doi.org/10.1016/s0022-3093(03)00450-2.

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34

Anastassakis, Giorgios, and César A. C. Sequeira. "Electrochemical and Surface Analytical Studies of Silver Deposits for Industrial Electroplating." Materials Science Forum 587-588 (June 2008): 829–33. http://dx.doi.org/10.4028/www.scientific.net/msf.587-588.829.

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For silver plating, mainly silver cyanide solutions are used and this is extensively treated in the literature. Yet, in view of the growing concern for environmental problems, they will have to be replaced because of their toxic properties. In the present work, the appropriateness of thiosulphate ) O S ( 2 3 2 − , a complexing agent for silver of common use in photographic applications, as an alternative for cyanide in electroplating baths is investigated. The kinetic characteristics of the reduction are determined, since they fix at which rate the plating can proceed. Prior to the kinetic study, requiring measurements in solutions of varying composition, the thermodynamic data on complex formation between Ag+ and − 2 3 2O S ions are analysed. And finally, the composition and the morphology of the silver deposits are examined as a function of the plating conditions. Electrochemical and analytical physical techniques are used.

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35

Wittwer, Paul D. "Epithermal Precious Metal Deposits in South Korea—History and Pursuit." SEG Discovery, no. 125 (April 1, 2021): 19–26. http://dx.doi.org/10.5382/segnews.2021-125.fea-01.

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Abstract The gold and silver endowment of Korea has historically been well known, with records alluding to production as far back as 1122 BC. The main gold production period was from 1925 to 1943 during the Japanese occupation of Korea, with more than 1 Moz recorded in 1939. Muguk was the most productive gold mining operation, located within the central region of South Korea, with a recorded 590 koz of gold produced from 1934 to 1998 (first mined in AD 912). The majority of the historical mining operations were closed by government order in 1943 during the Second World War and never reopened. A number of small mines operated between 1971 and 1998, with limited production during a period of gold prices generally lower than at present (~25–50% of current inflation adjusted prices, apart from a four-year period 1979–83). It is likely that significant resources remain within these historical mining areas. Gold-silver deposit types historically recognized and exploited in Korea include placers and orogenic and intrusion-related vein systems. Only more recently have epithermal vein and breccia systems been recognized. This is not surprising, given that the geologic and tectonic setting of the Southern Korean peninsula is prospective for epithermal precious metal deposits, spatially associated with basin-scale brittle fault systems in Cretaceous volcanic terranes. South Korea is an underexplored jurisdiction, with limited modern exploration and drilling until the mid-1990s, when Ivanhoe Mines Ltd. discovered the Gasado, Eunsan, and Moisan epithermal gold-silver deposits, all of which became mines. Exploration was limited for another 20 years until Southern Gold Ltd., an Australian Securities Exchange (ASX)-listed company, commenced regional-scale exploration for epithermal deposits, using a strategy similar to that successfully employed by Ivanhoe.

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36

Dimitrov, Aleksandar, Perica Paunovic, Orce Popovski, Dragan Slavkov, Zeljko Kamberovic, and Svetomir Hadzi-Jordanov. "Effect of non-stationary current regimes on the morphology of silver electrodeposits." Journal of the Serbian Chemical Society 74, no. 3 (2009): 279–89. http://dx.doi.org/10.2298/jsc0903279d.

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This work is concerned with the use of reverse current regimes in order to form small-grained and compact silver deposits during the electrorefining process. Several parameters were varied, i.e., i) anodic overpotential, ii) cathodic vs. anodic time ratio and iii) duration of the anodic pulse. After optimization of these parameters, phosphate ions were added and the electrolyte was stirred. The effects of a rise of the anodic overpotential on the grain sizes of the silver deposit and compactness were studied. Prolongation of the anodic time had a similar influence but with a decrease in current efficiency. An increase of the cathodic vs. anodic time ratio caused an enlargement of the grains and a decrease in the compactness of the deposit. Optimal morphological characteristics were obtained when PO3-4 were added and the electrolyte was stirred.

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37

Liu, Xiaoyan, Lin Li, Shengrong Li, M. Santosh, and Yujie Li. "Geochronology and Isotope Geochemistry of the Yingfang Pb-Zn-Ag Deposit: Implications for Large-Scale Metallogeny along the Northern Flank of the North China Craton." Minerals 11, no. 4 (March 29, 2021): 353. http://dx.doi.org/10.3390/min11040353.

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The northern flank of the North China Craton (NCC) hosts a linear zone of gold, molybdenum, silver, lead, and zinc polymetallic ore deposits. Among these, the Yingfang Pb-Zn-Ag deposit is located in the central part of the Yanshan–Liaoxi metallogenic belt (YLMB) which extends for approximately 1000 km and forms part of the major mineralized zone. In this study, we characterize the mineralization and trace the ore genesis based on new sulfur and lead isotopic geochemistry and evaluate the timing of mineralization from Rb-Sr isotope dating of sulfides. The pyrite δ34S values range from +3.2‰ to +5.8‰ with a mean at +4.07‰, close to the values of mantle and meteorite sulfur. The 206Pb/204Pb values range from 16.833 to 18.956, 207Pb/204Pb from 15.374 to 15.522, and 208Pb/204Pb from 37.448 to 37.928. Five samples of sulfide, from the Yingfang deposit, yield a Rb-Sr isochron age of 135.7 ± 4.1 Ma. This age is close to the age of the adjacent Niujuan Ag-Au deposit and the associated Er’daogou granite, suggesting a close relationship between magmatism and metallogeny in this region. The S and Pb isotopes of the regional silver polymetallic deposits show similar sources of ore-forming materials. According to a compilation of the available age data on the Mesozoic ore deposits in the northern flank of the NCC, we divide the mineralization into the following four periods: 240–205 Ma, 190–160 Ma, 155–135 Ma, and 135–100 Ma. Mesozoic magmatism and mineralization in the Yingfang deposit mainly took place at 245 Ma and 145–135 Ma. We correlate the Pb-Zn-Ag mineralization to metallogeny associated with large-scale inhomogeneous lithosphere thinning beneath the NCC.

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38

Parmley, R. T., C. S. Gilbert, D. A. White, and J. C. Barton. "Ultrastructural silver enhancement of Prussian blue-reactive iron in hematopoietic and intestinal cells." Journal of Histochemistry & Cytochemistry 36, no. 4 (April 1988): 433–40. http://dx.doi.org/10.1177/36.4.2450121.

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Prussian blue has been widely used to localize iron in a variety of tissues at the light and electron microscopic level. In the present study, thin sections of human marrow and blood cells and rat duodenal cells were exposed to silver proteinate (SP) after staining en bloc with acid ferrocyanide (AF), with and without prior iron saturation using iron nitrilotriacetate (FeNTA). Silver deposition was observed over Prussian blue-reactive sites and significantly enhanced sites of minimal AF and FeNTA-AF staining. AF-SP stain deposits were present in the cytoplasmic matrix, granules, and occasionally on the surfaces of macrophages, monocytes, and erythroblasts. FeNTA-AF-SP stained additional cytoplasmic and surface sites in erythroblasts and stained neutrophil granules intensely. Duodenal epithelium from iron-loaded rats demonstrated strong AF-SP staining of ferric iron in microvilli, apical cytoplasmic matrix, and lateral membranes. Similar preparations from iron-replete rats stained sparsely; however, intense AF-SP staining was observed after iron saturation with FeNTA. SP similarly enhanced luminal ferrous iron deposits stained with acid ferricyanide in rats given intraluminal ferrous iron. AF-SP stain deposits were removed by exposure of thin sections to NH4OH, KCN, or HNO3 but were not affected by prior exposure to HIO4 or NaBH4, consistent with a silver cyanide or complex stain precipitate rather than reduced silver or silver ferriferrocyanide. SP enhancement of Prussian blue allows identification of reactive sites not readily visualized with AF or FeNTA-AF alone, and offers the potential for differentiating AF staining from other deposits or organelles of comparable density.

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39

Guerrero, Saul. "Lead or Mercury, haifuki-hō or plata de azogue: the Environmental Dilemma in the History of Silver Refining." Asian Review of World Histories 7, no. 1-2 (January 23, 2019): 107–25. http://dx.doi.org/10.1163/22879811-12340048.

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Abstract In the sixteenth century the Spanish Empire would find itself owner and conqueror of the largest deposits of primary silver and mercury in the world, a geopolitical conjunction which would lead to the use of mercury at an industrial scale in the production of plata de azogue (silver by mercury) from silver sulfide deposits found in the Americas. Thus, two refining processes, the millennia-old two-stage smelting process based on lead and high temperatures, and the upstart based on mercury sine igne (without fire), came to share in nearly equal parts the aggregate global production of silver from the sixteenth to the final decade of the nineteenth century. These processes relied on the extensive use of two of the heavy metals most toxic to humans, and their anthropogenic emissions to the environment have caused impacts lasting over subsequent centuries. However, the successful use of haifuki-hō (smelting-cupellation process) in Japan to produce silver from silver sulfide ores with 0.2 percent silver content demonstrates that the extensive use of mercury by Spanish refiners in the New World was not the consequence of the geochemistry or silver content of the ores.

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40

Kovalenker, V. A., I. Ya Nekrasov, and V. S. Malov. "COPPER AND IRON SULFOSTANNATE MINERALS IN GOLD-SILVER DEPOSITS." International Geology Review 28, no. 12 (December 1986): 1443–59. http://dx.doi.org/10.1080/00206818609466380.

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41

McKinnon, Alastair D. "Immunogold-Silver Staining of Immune Deposits in Renal Biopsies." Journal of Histotechnology 16, no. 3 (September 1993): 243–47. http://dx.doi.org/10.1179/his.1993.16.3.243.

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42

Von Bargen, David. "Nevada Gold, Silver, and Copper Deposits and Their Minerals." Rocks & Minerals 74, no. 6 (November 1999): 405–14. http://dx.doi.org/10.1080/00357529909605179.

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43

Tian, Ying, Zheqi Li, Kun Shi, and Fenglin Yang. "Spontaneous and Electrochemical Reduction of Silver by Polypyrrole Deposits." Separation Science and Technology 43, no. 15 (October 17, 2008): 3891–901. http://dx.doi.org/10.1080/01496390802212625.

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44

Wu, C. Y., G. Bai, and L. M. Xu. "Types and distribution of silver ore deposits in China." Mineralium Deposita 28, no. 4 (September 1993): 223–39. http://dx.doi.org/10.1007/bf02421573.

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45

Shuyi, Liang, and Xia Hongyuan. "Silver and sulfosalt minerals in tungsten deposits, South China." Chinese Journal of Geochemistry 8, no. 2 (April 1989): 135–45. http://dx.doi.org/10.1007/bf02840437.

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46

Yoshikawa, Hisao, and Yukio Yoshida. "Localization of silver deposits on Pneumocystis carinii treated with Gomori's methenamine silver nitrate stain." Zentralblatt für Bakteriologie, Mikrobiologie und Hygiene. Series A: Medical Microbiology, Infectious Diseases, Virology, Parasitology 264, no. 3-4 (May 1987): 363–72. http://dx.doi.org/10.1016/s0176-6724(87)80057-3.

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47

Bornemann, T., and A. Otto. "Changes of the optical properties of “smooth” silver by silver deposits at low temperatures." Surface Science 211-212 (April 1989): 463–69. http://dx.doi.org/10.1016/0039-6028(89)90803-0.

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48

Bornemann, T., and A. Otto. "Changes of the optical properties of “smooth” silver by silver deposits at low temperatures." Surface Science Letters 211-212 (April 1989): A128. http://dx.doi.org/10.1016/0167-2584(89)90351-4.

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49

Berdnikov, N. V., V. G. Nevstruev, P. K. Kepezhinskas, V. O. Krutikova, N. S. Konovalova, and I. A. Astapov. "SILICATE, IRON OXIDE AND COPPER-GOLD-SILVER MICROSPHERULES IN ORES AND PYROCLASTICS OF THE KOSTENGINSKOYE IRON ORE DEPOSIT (RUSSIAN FAR EAST)." Tikhookeanskaya Geologiya 40, no. 3 (2021): 67–84. http://dx.doi.org/10.30911/0207-4028-2021-40-3-67-84.

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Iron-oxide ores and pyroclastics from the Kostenginskoye deposit in the Malyi Khingan (Russian Far East) contain numerous silicate, iron-oxide, and copper-gold-silver microspherules. Silicate spherules are composed of immiscible iron- and silica-rich glasses, gas cavities and mineral inclusions. Iron-oxide spherules include magnetite with minor ilmenite and Fe-rich silicate glass. Copper-gold-silver spherules contain inclusions predominantly of copper oxide compositions. The studied microspherules are considered to have formed during the rapid ascent of metal-silicate melts from depth and their degassing controlled by liquid immiscibility differentiation. The paper discusses the possible volcanic origin of iron-oxide ores and the associated noble metal mineralization for the deposits of this type.

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50

Franklin, J. M., S. A. Kissin, M. C. Smyk, and S. D. Scott. "Silver deposits associated with the Proterozoic rocks of the Thunder Bay District, Ontario." Canadian Journal of Earth Sciences 23, no. 10 (October 1, 1986): 1576–91. http://dx.doi.org/10.1139/e86-148.

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The silver deposits to the immediate north and west of Lake Superior are divided into three groups. The Mainland veins, the largest group, occur along a zone of normal faults near the western margin of the Proterozoic rocks of the Southern Province. The most economically productive deposits, the Island group, arc in or very near a northeast-trending swarm of gabbro dykes lying immediately offshore the northwestern shore of Lake Superior. The third group occurs near the western margin of the Port Coldwell alkalic complex; these veins are in a shear zone that cuts both Archean metasedimentary rocks and a Proterozoic diabase dyke. The Mainland deposits occur in the Rove shale, immediately below the contact with Logan diabase sills. The veins locally extend upwards into the sills, but the silver-bearing portions, consisting of acanthite and native silver associated with base-metal sulphides, fluorite, barite, quartz, and calcite, are largely bounded by locally silicified shale. The Island veins, typified by the Silver Islet mine, are in fractures perpendicular to the gabbro-dyke host rocks. These veins contain both native silver and acanthite, associated with a Ni–Co sulpharsenide suite and the same mineral assemblage as the Mainland deposits. The veins near Coldwell are rich in sphalerite and galena.Lead-isotope data indicate that the Mainland and Island veins are genetically related and that the Mainland veins formed from an inhomogeneous fluid. Two-stage calculations indicate an early Proterozoic source rock, possibly the Rove shale. The Island veins are more isotopically homogeneous, and their metals may have been derived partially from the gabbro. The Coldwell veins contain lead that is less radiogenic than that of the other two groups and is possibly derived from the adjacent Archean rocks. All three groups of deposits have isotopic compositions that are much less uranogenic and more thorogenic than the nearby Pb–Zn–Ba veins of the Dorion area. Preliminary fluid-inclusion data from the Mainland veins indicate that deposition occurred from a fluid whose temperature varied from approximately 200 °C to more than 400 °C; deposition occurred during boiling induced by adiabatic expansion of the fluid at relatively shallow crustal depths. The Mainland veins developed in the shale (rather than the diabase), as its high fissility, and hence permeability, made it susceptible to intense fracturing by the expanding fluid. Both the Mainland and Island groups were deposited in structures formed dominantly by listric normal faulting during late stages of intracontinental rifting. Heat was supplied by abundant mafic intrusions that formed coincident with rifting. The ore fluid was probably formed as a result of metamorphic dewatering, with metals released to the fluid because of silicate and sulphide recrystallization.

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