Journal articles: '040306 Mineralogy and Crystallography'

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SUGIYAMA, Kazumasa, and Akihiko NAKATSUKA. "Mineralogy and Crystallography." Nihon Kessho Gakkaishi 56, no. 3 (2014): 149. http://dx.doi.org/10.5940/jcrsj.56.149.

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Gurzhiy, Vladislav V. "Mineralogical Crystallography." Crystals 10, no. 9 (September 11, 2020): 805. http://dx.doi.org/10.3390/cryst10090805.

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Gurzhiy, Vladislav V. "Mineralogical Crystallography Volume II." Crystals 12, no. 11 (November 13, 2022): 1631. http://dx.doi.org/10.3390/cryst12111631.

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Hawthorne, Frank C. "Mathematical crystallography, reviews in mineralogy, vol. 15." Geochimica et Cosmochimica Acta 50, no. 7 (July 1986): 1565. http://dx.doi.org/10.1016/0016-7037(86)90333-9.

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Alves, Carlos, Carlos Figueiredo, and Jorge Sanjurjo-Sánchez. "Virtual Models for Crystallography Teaching in Mineralogy: Some Suggestions." Environmental Sciences Proceedings 5, no. 1 (December 1, 2020): 10. http://dx.doi.org/10.3390/iecg2020-08738.

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Crystallography concepts are usually among the most demanding subjects for Mineralogy students. Traditional onsite teaching of Mineralogy starts with physical models of crystal polyhedra and frequently also includes the observation of models of crystal structures. These teaching strategies could be difficult to implement under pandemic situations like the present one. But they also have other disadvantages under the usual access conditions as their use by the students is restricted by the number of students in relation to the number of models and by the availability of the models and teaching staff. Additionally, onsite teaching can pose challenges to both students and teachers with temporal or permanent disabilities. We consider here some possibilities of teaching with virtual models of crystal polyhedra, twinning, and crystal structures, based on some of the available freeware options and considering the main concepts taught in the usual Mineralogy syllabus.

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Voytehovskiy, Yuri. "From teaching experience. XI. History and philosophy at the crystallography and mineralogy courses." Vestnik of geosciences, no. 6 (August 12, 2022): 44–52. http://dx.doi.org/10.19110/geov.2022.6.5.

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The article is devoted to the history and philosophy of crystallography and mineralogy. Composed from individual plots, in general, it shows a wide range of topics advisable to discuss with geological students at the Crystallography and Mineralogy courses. This can be done in the framework of the lectures during pauses recommended by the current pedagogical methods, or optionally. An extensive list of primary sources and fresh literature is given to prepare conversations. Their goal is attracting students to read a serious literature on the history and philosophy of the studied sciences.

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Yuan, Xue, Li Guowu, and Yang Guangming. "Mineralogy and Crystallography of Stokesite From Inner Mongolia, China." Canadian Mineralogist 55, no. 1 (January 2017): 63–74. http://dx.doi.org/10.3749/canmin.1600045.

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Plášil, Jakub. "Mineralogy, Crystallography and Structural Complexity of Natural Uranyl Silicates." Minerals 8, no. 12 (November 27, 2018): 551. http://dx.doi.org/10.3390/min8120551.

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Naturally occurring uranyl silicates are common constituents of the oxidized parts (i.e., supergene zone) of various types of uranium deposits. Their abundance reflects the widespread distribution of Si4+ in the Earth’s crust and, therefore, in groundwaters. Up to date, 16 uranyl silicate minerals are known. Noteworthy is that the natural uranyl silicates are not extremely diverse regarding their crystal structures; it is a result of possible concentrations (activity) of Si4+ in aqueous solutions derived from dissolution of primary Si minerals or the composition of late hydrothermal fluids. Therefore, in natural systems, we distinguish in fact among two groups of uranyl silicate minerals: uranophane and weeksite-group. They differ in U:Si ratio (uranophane, 1:1; weeksite, 2:5) and they form under different conditions, reflected in distinctive mineral associations. An overview of crystal-chemistry is provided in this paper, along with the new structure data for few members of the uranophane group. Calculations of the structural complexity parameters for natural uranyl silicates are commented about as well as other groups of uranyl minerals; these calculations are also presented from the point of view of the mineral paragenesis and associations.

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Kahlenberg, Volker, Clivia Hejny, and Johan P. R. deVilliers. "How crystallography can assist process mineralogy – two metallurgical examples." Acta Crystallographica Section A Foundations and Advances 72, a1 (August 28, 2016): s60. http://dx.doi.org/10.1107/s2053273316099095.

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Nakamura, Tomoki, Takaaki Noguchi, and Masahiko Tanaka. "Mineralogy and crystallography of return samples from primitive asteroids." Acta Crystallographica Section A Foundations and Advances 73, a2 (December 1, 2017): C1299. http://dx.doi.org/10.1107/s2053273317082766.

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Matkovskyi, Orest, and Yevheniia Slyvko. "Academician Yevhen Lazarenko scientific readings and their contribution to the development of modern mineralogy." Mineralogical Collection 71, no. 1 (2021): 3–27. http://dx.doi.org/10.30970/min.71.01.

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Periodic Scientific Readings named after Academician Yevhen Lazarenko were offered by his students and followers from the Department of Mineralogy of Ivan Franko National University of Lviv and Ukrainian Mineralogical Society. The corresponding decision was made by the participants of the scientific conference (1997) dedicated to the 80th anniversary of Ye. Lazarenko. After all, perpetuating the memory of outstanding scientists and assessing the importance of their contribution to the development of basic science is impossible without scientific forums organized in their honour. Eleven such Scientific Readings have already taken place, in which scientists, teachers, geologists-practitioners, graduate students and students of Ukraine and other countries took part. Participants of the Readings discussed various problems of mineralogy and related sciences (crystallography, geochemistry, petrography, the study of mineral deposits, etc.) and identified the role of Ye. Lazarenko and his Scientific Mineralogical School in the development of mineralogy in Ukraine and abroad, because, being patriot of Ukraine, Yevhen Kostiantynovych believed that science has no borders. Almost all Readings were thematic, dealing with the problems of regional and genetic mineralogy, mineralogical crystallography, applied mineralogy, history of science, as well as various aspects of space mineralogy, mineral ontogeny, thermobarogeochemistry, biomineralogy, technological and ecological mineralogy. Their materials have been published in separate editions and in the “Mineralogical Collection”, founded by Ye. Lazarenko. The results of the research presented during the Academician Yevhen Lazarenko Scientific Readings and published in different editions are extremely diverse and important both from a theoretical and applied point of view. Undoubtedly, they significantly enriched the mineralogical science not only in Ukraine but also in general, and testified to the fundamental nature of the scientific heritage of the outstanding scientist of the twentieth century – Academician Yevhen Lazarenko. Key words: Academician Yevhen Lazarenko, Scientific Readings, mineralogy, scientific directions of modern mineralogy, history of science, Ivan Franko National University of Lviv.

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Bucio, Lauro, and Irma Araceli Belio-Reyes. "Some Crystallographic Activities Organized in Mexico." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1295. http://dx.doi.org/10.1107/s205327331408704x.

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The Mexican Society of Crystallography (SMCr) has 19 years old; 14 Regional Delegations (red points in the map below); has celebrated six national meetings (each one with audiences of around 250, red points with circles in the map below); and several courses, workshops, conferences along its lifespan. Also around 50 monographs have been produced, with some videos, games and souvenirs related with crystallography. A lot of them have been designed for improving the teaching of crystallography in graduate and postgraduate programs. Visits to the giant crystals of gypsum in the locality of Naica in the mexican state of Chihuahua, were organized by the SMCr with the kindly permission of Peñoles Company. Documents concerning to the history of crystallography in Mexico have been published by A. Cordero-Borboa [1-3]. On 2014, the SMCr will celebrate the IYCr,with organizing several activities and its seventh national meeting. With other Latin American countries will join to the initiative of found the Latin American Crystallographic Association (LACA) and its incorporation as Regional Associate of the International Union of Crystallography (IUCr). In the next images, circling the map of Mexico, starting from the upper left and following clockwise sense: cave of swords; gem (workshop on gemology); giant crystals of gypsum in Naica; crystal drawings (mineralogy for kids workshop); workshop on the Rietveld method; mineralogy for kids workshop; workshop on crystal growth of proteins.

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Kovrugin, Vadim M., Marie Colmont, Olivier Mentré, Oleg I. Siidra, and Sergey V. Krivovichev. "Modular crystallography of novel copper selenites and selenates: experimental mineralogy." Acta Crystallographica Section A Foundations and Advances 73, a2 (December 1, 2017): C84. http://dx.doi.org/10.1107/s2053273317094876.

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Rapp, George. "William Whewell: Professor of Mineralogy [And Crystallography] Cambridge University 1828-1834." Earth Sciences History 33, no. 1 (January 1, 2014): 1–9. http://dx.doi.org/10.17704/eshi.33.1.2v50746h24325460.

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Today philosophers, scientists, and other scholars know William Whewell as a major figure in the history and philosophy of science and as a wordsmith who coined many scientific terms still in use. Mineralogists are likely aware that there is a mineral Whewellite. Whewell entered the field of mineralogy just as it was coming of age as a science. He was a life-long academic at Trinity College, Cambridge University where he served as Professor of Mineralogy, later as Professor of Moral Philosophy, and rose to become Master of the College. His major contributions to earth science were in mathematical crystallography and tidal phenomena. Whewell's wide-ranging ideas and research qualify him as a mid-nineteenth century polymath.

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PAVLYSHYN, V. I. "Mineralogy in Independent Ukraine (1991-2021)." Mineralogical Journal 43, no. 3 (2021): 3–24. http://dx.doi.org/10.15407/mineraljournal.43.03.003.

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This article discusses the state of mineralogical research in independent Ukraine in the period from 1991 to 2021. The main achievements in various Earth sciences disciplines, including regional, systematic and genetic mineralogy, the chemistry and physics of minerals, mineralogical crystallography, bio- and nanomeralogy, experimental, space and applied mineralogy, and technical studies are considered. Four world-famous research groups and disciplines are notable. They are: i) regional and mineralogical led by academician Yevhen Lazarenko, ii) thermobarogeochemical studies led by professor Mykola Yermakov, iii) crystal chemistry led by academician Oleksandr Povarennykh, and iv) mineral physics led by professors Ivan Matyash, Oleksiy Platonov, and Arkady Tarashchan. Problems facing mineralogy including personnel, scientific, and applied are briefly discussed in the "Conclusion" section.

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Fiala, Jaroslav, Vlastimil Bodák, and Miroslav Dubovinský. "Powder Diffraction – A Journal Citation Study." Powder Diffraction 6, no. 3 (September 1991): 153–55. http://dx.doi.org/10.1017/s0885715600017309.

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AbstractCitation analysis of the articles that appeared in the first five volumes of the journal Powder Diffraction showed that it is clearly a journal of crystallography with strong ties to materials science, mineralogy and analytical chemistry. This specific orientation makes Powder Diffraction invaluable in the existing network of scientific journals.

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Voytekhovsky, Yu L. "From teaching experience. VII. Subordination of symmetry groups and crystallographic criterion of harmony." Vestnik of Geosciences 2 (2021): 19–22. http://dx.doi.org/10.19110/geov.2021.2.4.

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It is shown by the example of the fences of Saint Petersburg that they combine the borders of all seven symmetry groups in different ways. A criterion is proposed: a lattice is harmonious if the symmetry groups of the borders are subordinate, otherwise it is eclectic. According to the author’s experience, such an approach on the border of crystallography and architecture facilitates the perception of the topic on the subordination of 32 point symmetry groups in the university course of crystallography. The article is dedicated to the memory of the outstanding scientist and popularizer of mineralogy Professor A. G. Bulakh.

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Pushcharovsky, D. Yu. "The Modern Crystallography: Is It Useful for the Earth’s Sciences?" Moscow University Bulletin. Series 4. Geology, no. 1 (December 15, 2022): 3–23. http://dx.doi.org/10.33623/0579-9406-2023-1-3-23.

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Formed in XVII century at the junction between mineralogy and mathematics subsequently crystallography is considered as the science which is closer to physics, chemistry, biology and even to medicine. Due to this fact, the community, associated with the Earth’s sciences, accepts it with some restraint. The importance of the most advanced crystallographic approaches, the results obtained and the new insights which contribute the further development of the new scientific ideas about the composition and the structure of the Earth and some terrestrial planets are considered.

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ARESHIN, A. V., O. E. EFIMOV, and V. D. NAUMOV. "DEPARTMENT OF GEOLOGY OF TIMIRYAZEV AGRICULTURAL ACADEMY: HISTORY OF FOUNDATION AND DEVELOPMENT." Izvestiâ Timirâzevskoj selʹskohozâjstvennoj akademii, no. 3 (2022): 148–72. http://dx.doi.org/10.26897/0021-342x-2022-3-148-172.

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When the Petrovsky Agricultural and Forestry Academy was founded, the Department of Mineralogy and Geognosy was established, along with other departments. The course of geology, taught at the department, had an applied significance as well as a huge ideological and educational value. During its existence, a scientific and pedagogical school in the field of crystallography, mineralogy and geology was established. The research of agronomic ores, linking the geological and agronomic sciences is of great importance. For a century and a half since its foundation, the department has gone through a difficult path from purely descriptive geological research (lithological-petrographic, paleontological) to complex interdisciplinary (paleolandscape and adaptive landscape) research.

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Becker, M., J. de Villiers, and D. Bradshaw. "The Mineralogy and Crystallography of Pyrrhotite from Selected Nickel and PGE Ore Deposits." Economic Geology 105, no. 5 (August 1, 2010): 1025–37. http://dx.doi.org/10.2113/econgeo.105.5.1025.

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Marabello, Domenica, Angelo Agostino, Piera Benna, Giovanna Dinardo, Carlo Lamberti, and Fernando Cámara. "CrisDi School: disseminating crystallography in Piedmont, Italy." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1277. http://dx.doi.org/10.1107/s2053273314087221.

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The Interdepartmental Research Centre for the Development of Crystallography (CrisDi) aims to be an institution of reference for researchers at the University of Turin interested on the field of diffraction (X-rays, neutrons and electrons), to promote the knowledge and dissemination of crystallography, and to facilitate the access to available laboratory instrumentation (diffractometers and TEM) and to large scale facilities (synchrotron and neutron sources). CrisDi hosts scientists with interest in the fields of solid state chemistry and physics, organic, inorganic, organometallic and theoretical chemistry, mineralogy, biology, pharmaceutical and agricultural sciences. The Centre encourages the design and the development of new methodologies and applications, and supports the enhancement of the available instruments. The submission of proposals at large scale instruments is encouraged specially for young researchers and PhD students. The cultural and scientific interchange among crystallographers coming from different disciplines is strongly encouraged by CrisDi. A main task of the CrisDi is the annual organization of a post-grade level School with a series of courses dedicated to: (i) basic level crystallography (symmetry, theory of diffraction, crystal-chemistry), diffraction techniques (single crystal and powder X-ray diffraction, neutron and electron scattering); (ii) advanced level (high temperature and high pressure structural studies, macromolecular crystallography, time resolved crystallography and kinetic studies); (iii) spectroscopic approaches (XAFS, XANES, XES and NMR) in crystallography. The school, which is held every year in May for about 20 ECTS equivalent, has no tuition fees and is also open to non-academia people.

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Garcia-Granda, Santiago, and Laura Roces. "IYCr2014: Ongoing Activities around the ECA area." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1300. http://dx.doi.org/10.1107/s2053273314086999.

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As the International Year of Crystallography is going on, the crystallographic community is actively involved in a number of activities and events to connect crystallography and society. The European Area, where the seminal discoveries took place, combines the traditional out-reach activities carried out during the last few years with several new activities to make crystallography and crystallization attractive to the public in general. The crystal growing competitions, involving high schools, organized since 2008 in Spain, are in 2014 very popular in the ECA Area. Since 2011, a Summer Scientific Campus has been held at the University of Oviedo in which the students develop a research project that incorporates crystallography as the core theme (X-Ray diffraction in the Forensic Science, Crystallisation and Mineralogy Workshops) [1]. An extension of that is the Spanish program for IYCr2014 "Science, Crystals and Society" [2]. For the European activities, the ECA Executive Committee created the IYCr2014 Coordination Committee, to gather initiatives in the ECA area and to be a link with the IUCr worldwide supervision of IYCr2014. "Discovering", "Getting involved" and "Communicating" are the three key points to connect scientists and society. The main objective of this project is to integrate and disseminate the science of crystallography into the European society, particularly among students, boosting the European dimension of the Project. "Discovering", "Getting involved" and "Communicating" are the three key points that will connect scientists and society. This European platform (http://www.iycr2014.eu) and the associated social networks content are the European links between crystallography and society using a number of tools: A dedicated IP/TV, ITunesU Chanel, or the Google Course Builder tool platform. Acknowledgements: Financial support from Ministerio de Economía y Competitividad de España (MAT2010-15094, Factoría de Cristalización–Consolider Ingenio 2010) and ERDF.

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INSLEY, JANE. "ILLUSTRATING THE IDEAL: CRYSTAL MODELS AND ILLUSTRATIONS IN THE EARLY NINETEENTH CENTURY." Earth Sciences History 37, no. 2 (January 1, 2018): 333–41. http://dx.doi.org/10.17704/1944-6178-37.2.333.

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In the stores of museums and university departments of mineralogy and crystallography, there are collections of sets of models of crystal shapes. Representing the external form of natural specimens, their use was for identification and demonstration purposes, by scientists, teachers and students from the late eighteenth century onwards. Whilst studying crystal model collections at the National Museums Scotland in Edinburgh, I came across the illustration work of Miss Delvalle Lowry. Her name, along with that of her father Wilson, appeared on plates illustrating an 1820 textbook by Nathaniel Larkin, a London teacher of solid geometry. Miss Lowry married the painter John Varley in 1825 and wrote a number of mineralogical texts that were reprinted through the first half of the nineteenth century. Delvalle Lowry was able to enjoy this career not least as a result of her ability to draw. The role of the Society of Arts in encouraging both drawing and the study of crystallography may well have been a feature of her success.

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Prince, E. "Mathematical crystallography – an introduction to the mathematical foundations of crystallography. Reviews in Mineralogy, Vol. 15 (revised). by M. B. Boisen and G. V. Gibbs." Acta Crystallographica Section A Foundations of Crystallography 49, no. 5 (September 1, 1993): 791. http://dx.doi.org/10.1107/s0108767393002223.

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Evans, John Spencer, Ram Samudrala, Tiffany R. Walsh, Ersin Emre Oren, and Candan Tamerler. "Molecular Design of Inorganic-Binding Polypeptides." MRS Bulletin 33, no. 5 (May 2008): 514–18. http://dx.doi.org/10.1557/mrs2008.103.

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AbstractControlled binding and assembly of peptides onto inorganic substrates is at the core of bionanotechnology and biological-materials engineering. Peptides offer several unique advantages for developing future inorganic materials and systems. First, engineered polypeptides can molecularly recognize inorganic surfaces that are distinguishable by shape, crystallography, mineralogy, and chemistry. Second, polypeptides are capable of self-assembly on specific material surfaces leading to addressable molecular architectures. Finally, genetically engineered peptides offer multiple strategies for their functional modification. In this article, we summarize the details and mechanisms involved in combinatorial-polypeptide sequence selection and inorganic-material recognition and affinity, and outline experimental and theoretical approaches and concepts that will help advance this emerging field.

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Voytehovskiy, Yuriy. "From teaching experience. IX. Entropy of the convex polyhedron." Vestnik of geosciences, no. 1 (March 17, 2022): 44–53. http://dx.doi.org/10.19110/geov.2022.1.4.

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The article is devoted to the applications of the entropy category in the natural sciences, mainly in mineralogy and crystallography to describe the complexity of mineral parageneses and crystal structures. It is shown that thermodynamic, informational and statistical entropy, defined independently in different disciplines, do not copy each other. They are not recalculated into each other and agree at the level of general principles. Statistical entropy as a measure of the complexity of systems characterized by probability distributions of parameters is always their convolution with loss of information. As a scale of complexity, it is unevenly curved in different areas of the probability field. The article is dedicated to the 85th anniversary of the birth of N. P. Yushkin.

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Leisegang, Tilmann, Aleksandr A. Levin, and Andreas Kupsch. "From the Ritter pile to the aluminum ion battery – Peter Paufler’s academic genealogy." Zeitschrift für Kristallographie - Crystalline Materials 235, no. 11 (November 26, 2020): 481–511. http://dx.doi.org/10.1515/zkri-2020-0063.

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AbstractThis article highlights Peter Paufler’s academic genealogy on the occasion of his 80th birthday. We describe the academic background since 1776, which covers 11 generations of scientists: Ritter, Ørsted, Han-steen, Keilhau, Kjerulf, Brøgger, Goldschmidt, Schulze, Paufler, Meyer, and Leisegang. The biographies of these scientists are described in spotlight character and references to scientists such as Dehlinger, Ewald, Glocker, Röntgen, Vegard, Weiss, and Werner are given. A path is drawn that begins in the Romanticism with electrochemistry and the invention of what is probably the first accumulator. It leads through the industrialization and the modern geology, mineralogy, and crystallography to crystal chemistry, metal and crystal physics and eventually returns to electrochemistry and the aluminum-ion accumulator in the era of the energy transition. The academic genealogy exhibits one path of how crystallography develops and specializes over three centuries and how it contributes to the understanding of the genesis of the Earth and the Universe, the exploration of raw materials, and the development of modern materials and products during the industrialization and for the energy transition today. It is particularly characterized by the fields of physics and magnetism, X-ray analysis, and rare-earth compounds and has strong links to the scientific landscape of Germany (Freiberg) and Scandinavia, especially Norway (Oslo), as well as to Russia (Moscow, Samara, St. Petersburg). The article aims at contributing to the history of science, especially to the development of crystallography, which is the essential part of the structural science proposed by Peter Paufler.

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Nespolo, Massimo. "Review of Jakub Plášil, Juraj Majzlan and Sergey Krivovichev (eds.) (2017): Mineralogical Crystallography. EMU Notes in Mineralogy, Vol. 19." European Journal of Mineralogy 30, no. 3 (September 1, 2018): 655–56. http://dx.doi.org/10.1127/ejm/2018/0030-2778.

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Casas, Lluís. "Three-dimensional-printing aids in visualizing the optical properties of crystals." Journal of Applied Crystallography 51, no. 3 (April 13, 2018): 901–8. http://dx.doi.org/10.1107/s1600576718003709.

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Crystal optics is an essential topic in mineralogy and is also relevant at postgraduate level in solid-state chemistry and physics. The emergence of low-cost three-dimensional-printing technologies makes possible the creation of tangible objects for multiple educational purposes. Within the field of crystallography and chemistry, some examples of applications of such educational objects have been recently published. These were intended for teaching and learning of crystal and molecular symmetry concepts. In this paper, three-dimensional-printing applications have been extended to crystal optics. A number of tangible models of optical indicatrices have been designed and printed. These models were conceived as dissection puzzles and allow students to actively work on assembling them and analyzing their geometrical features and relevant sections. The STL files of the presented models are made available with this paper.

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Diella, Valeria, Federico Pezzotta, Rosangela Bocchio, Nicoletta Marinoni, Fernando Cámara, Antonio Langone, Ilaria Adamo, and Gabriele Lanzafame. "Gem-Quality Tourmaline from LCT Pegmatite in Adamello Massif, Central Southern Alps, Italy: An Investigation of Its Mineralogy, Crystallography and 3D Inclusions." Minerals 8, no. 12 (December 13, 2018): 593. http://dx.doi.org/10.3390/min8120593.

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In the early 2000s, an exceptional discovery of gem-quality multi-coloured tourmalines, hosted in Litium-Cesium-Tantalum (LCT) pegmatites, was made in the Adamello Massif, Italy. Gem-quality tourmalines had never been found before in the Alps, and this new pegmatitic deposit is of particular interest and worthy of a detailed characterization. We studied a suite of faceted samples by classical gemmological methods, and fragments were studied with Synchrotron X-ray computed micro-tomography, which evidenced the occurrence of inclusions, cracks and voids. Electron Microprobe combined with Laser Ablation analyses were performed to determine major, minor and trace element contents. Selected samples were analysed by single crystal X-ray diffraction method. The specimens range in colour from colourless to yellow, pink, orange, light blue, green, amber, brownish-pink, purple and black. Chemically, the tourmalines range from fluor-elbaite to fluor-liddicoatite and rossmanite: these chemical changes occur in the same sample and affect the colour. Rare Earth Elements (REE) vary from 30 to 130 ppm with steep Light Rare Earth Elemts (LREE)-enriched patterns and a negative Eu-anomaly. Structural data confirmed the elbaitic composition and showed that high manganese content may induce the local static disorder at the O(1) anion site, coordinating the Y cation sites occupied, on average, by Li, Al and Mn2+ in equal proportions, confirming previous findings. In addition to the gemmological value, the crystal-chemical studies of tourmalines are unanimously considered to be a sensitive recorder of the geological processes leading to their formation, and therefore, this study may contribute to understanding the evolution of the pegmatites related to the intrusion of the Adamello pluton.

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Whittaker, E. J. W. "M. B. Boisen and G. V. Gibbs. Mathematical Crystallography: An introduction to the mathematical foundations of crystallography. Washington D.C. (Mineralogical Society of America: Reviews in Mineralogy, Vol. 15), 1985. xii + 406 pp. Price $18.00." Mineralogical Magazine 51, no. 359 (March 1987): 180. http://dx.doi.org/10.1180/minmag.1987.051.359.30.

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Daran, Jean-Claude, Lionel Mourey, Anne-Magali Seydoux, and Nicolas Ratel-Ramond. "IYCr2014 in the « Midi-Pyrénées » Region, France." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C1297. http://dx.doi.org/10.1107/s2053273314087026.

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To promote crystallography through the "Midi-Pyrénées" Region, our association, « Les Cristallographes en Midi-Pyrénées » has scheduled different events from October 2013 until the end of 2014. These events will cover scientific demonstrations and/or lectures open to the general public. 1) Events - The Novela (7-12 October 2013), organized by the Toulouse-Metropole, is an event whose major goal is to share knowledge, in all its diversity, in a festive and popular spirit. It aimed at pupils and students as well as the general public. This will be performed once again in October 2014. - The "Kiosque-Actu" at the Toulouse Museum provides an opportunity to inquire and to exchange with researchers on a scientific topical subject. On the 2nd of February 2014, researchers coming from several laboratories in Toulouse (CEMES, CIRIMAT, GET, IPBS, and LCC; from the CNRS and the Paul Sabatier University) and involved in all domains of X-ray diffraction (Biology, Mineralogy, Chemistry, Materials, etc.) came to meet the general public and to demonstrate the importance of crystallography. Exhibition "Voyage dans le cristal / Journey within a crystal" at (i) the Philadelphe Thomas Museum in Gaillac (14 February-4 May 2014) and (ii) at the library of the Paul Sabatier University (from the 1st of September until the end of the year). Panels from this exhibition have been/will be also displayed during all events mentioned above. 2) Conferences - Maryvonne Hervieu (ENSICAEN, Caen, France), 17 February 2014, "Des cristaux et des hommes / Of crystals and men". - Jean-Claude Daran (LCC, Toulouse, France), 20 February 2014, "Les cristaux de Louis Pasteur / Louis Pasteur's crystals". - Lionel Mourey (IPBS, Toulouse, France), 27 February 2014, "Des cristaux au secours de la médecine / Crystals to help medicine". - Anne-Magali Seydoux (GET, Toulouse, France), 10 April 2014, "Effets de la radioactivité sur les structures des minéraux / Effects of radioactivity on the structure of minerals".

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Nespolo, Massimo. "Crystallography and Mineralogy. By Kiyoshi Fujino. Ky\bf\overline oritsu, 2015. Hardcover, X+180. Price Yen 3600. ISBN 978-4-320-04719-8." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 72, no. 1 (January 30, 2016): 164–66. http://dx.doi.org/10.1107/s2052520615023483.

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Salje, Ekhard K. H. "Ferroelastic Twinning in Minerals: A Source of Trace Elements, Conductivity, and Unexpected Piezoelectricity." Minerals 11, no. 5 (April 30, 2021): 478. http://dx.doi.org/10.3390/min11050478.

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Ferroelastic twinning in minerals is a very common phenomenon. The twin laws follow simple symmetry rules and they are observed in minerals, like feldspar, palmierite, leucite, perovskite, and so forth. The major discovery over the last two decades was that the thin areas between the twins yield characteristic physical and chemical properties, but not the twins themselves. Research greatly focusses on these twin walls (or ‘twin boundaries’); therefore, because they possess different crystal structures and generate a large variety of ‘emerging’ properties. Research on wall properties has largely overshadowed research on twin domains. Some wall properties are discussed in this short review, such as their ability for chemical storage, and their structural deformations that generate polarity and piezoelectricity inside the walls, while none of these effects exist in the adjacent domains. Walls contain topological defects, like kinks, and they are strong enough to deform surface regions. These effects have triggered major research initiatives that go well beyond the realm of mineralogy and crystallography. Future work is expected to discover other twin configurations, such as co-elastic twins in quartz and growth twins in other minerals.

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Altomare, Angela, Nicola Corriero, Corrado Cuocci, Aurelia Falcicchio, Anna Moliterni, and Rosanna Rizzi. "Main features of QUALX2.0 software for qualitative phase analysis." Powder Diffraction 32, S1 (March 14, 2017): S129—S134. http://dx.doi.org/10.1017/s0885715617000240.

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The phase identification of a polycrystalline mixture by X-ray powder diffraction data is often requested for studying materials interesting to different scientific and technological fields: chemistry, pharmaceutics, mineralogy, archeometry, forensic science, etc. The availability of user friendly computer programs, able to carry out qualitative phase analysis in efficient and possibly automatic way, is extremely useful to the scientific community involved in powder diffraction. QUALX2.0, the evolution of QUALX, is a freely distributed software for qualitative phase analysis. Based on the traditional search–match method, it is able to manage both a commercial database (PDF-2 maintained by ICDD), and a freely available database (POW_COD generated by the structure information contained in the Crystallography Open Database). QUALX2.0 is continuously improved in terms of computing and graphic tools. Correspondingly, the database POW_COD is suitably modified to make efficient the operations of search. The search–match approach can be facilitated by the use of restraints, when available, involving the chemical composition, the kind of compound(s) (e.g., organic, inorganic, etc.), the symmetry (space group, crystal system), the unit-cell parameters and/or volume, the crystal properties (measured and/or calculated crystal density, crystal color). An outline of the main features of QUALX2.0 and an example of application is described.

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Liu, Dongna, Yun Zhang, Anchao Zhou, Emmanuel Nnachi, Shuting Huo, and Qi Zhang. "The Kaolinite Crystallinity and Influence Factors of Coal-Measure Kaolinite Rock from Datong Coalfield, China." Minerals 12, no. 1 (December 30, 2021): 54. http://dx.doi.org/10.3390/min12010054.

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In order to ascertain the kaolinite crystallinity of Carboniferous Permian coal-measure kaolinite rocks, seven groups of fresh samples were collected from below the ground in the Xiaoyu mine, Datong coalfield. Microscopy, X-ray diffraction (XRD), differential thermal analysis (DTA), infrared (IR) spectroscopy and X-ray fluorescence (XRF) spectrometry methods were applied to the samples. The petrographic analysis results show that the kaolinite rocks are characterized as compact, phaneritic, clastic, sand-bearing, sandy and silty types; the kaolinite content in the Shanxi formation and upper Taiyuan formations was more than 95%, while it was 60–90% in the middle and lower Taiyuan formations. Based on the Hinckley index and the features of XRD, DTA and IR of kaolinites, crystallinity was classified as having three grades: ordered, slightly disordered and disordered. The kaolinites’ SiO2/Al2O3 molar ratio was about 1.9–5.7, with a chemical index of alteration (CIA) of about 95.4–99.5. This research suggests that the kaolinite crystallinity correlates positively to its clay mineral content, purity and particle size, which are also related to the SiO2/Al2O3 molar ratio and CIA. The original sedimentary environment and weathering have a direct influence on kaolinite crystallinity, and the existence of organic matter is conducive to the stable existence of kaolinite. The study results have significance for the extraction and utilization of coal-measure kaolinite and the development of kaolinite crystallography and mineralogy.

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Beagley, B., and J. R. Helliwell. "Durward W. J. Cruickshank. 7 March 1924—13 July 2007." Biographical Memoirs of Fellows of the Royal Society 65 (September 5, 2018): 71–87. http://dx.doi.org/10.1098/rsbm.2018.0018.

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Durward Cruickshank was an eminent crystallographer and structural chemist, whose mathematical abilities transformed the precision of the molecular structures determined in three dimensions by X-ray crystal structure analysis. This technique is very widely applied to determine the three-dimensional (3D) shapes of molecules of importance in biology, chemistry, mineralogy, materials science and physics. Durward's first publication was on this topic, with Sir Gordon Cox. It represents a lifelong interest of Durward in the precision of crystal structure analysis and extended also to gas-phase electron diffraction. His research publications spanned an amazing 60 years and he had a direct influence on over 900 000 chemical crystal structures, the number currently determined and held in the Cambridge Structure Database alone. Proteins took his attention for research in his last decade, and his diffraction precision index (DPI) indicator of the precision of a protein structure is added regularly to entries in the Protein Data Bank. In his ‘retirement’ he contributed, with one of the authors of this memoir, J.R.H., and various colleagues in the UK and the USA, to the development of the ‘Laue diffraction’ white beam synchrotron method, applied today to sub-nanosecond X-ray crystallography measurement techniques, and also to study micron sized, i.e. tiny, crystal samples. The method has also led ultimately to more effective exploitation of neutron beams from research reactors for crystallographic studies of the hydrogenation details of molecules.

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Nestola, F., A. Guastoni, L. Bindi, and L. Secco. "Dalnegroite, Tl5–xPb2x(As,Sb)2l–xS34, a new thallium sulphosalt from Lengenbach quarry, Binntal, Switzerland." Mineralogical Magazine 73, no. 6 (December 2009): 1027–32. http://dx.doi.org/10.1180/minmag.2009.073.6.1027.

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AbstractDalnegroite, ideally Tl4Pb2(As12Sb8)Σ20S34, is a new mineral from Lengenbach, Binntal, Switzerland. It occurs as anhedral to subhedral grains up to 200 μm across, closely associated with realgar, pyrite, Sb-rich seligmanite in a gangue of dolomite. Dalnegroite is opaque with a submetallic lustre and shows a brownish-red streak. It is brittle; the Vickers hardness (VHN25) is 87 kg mm-2(range: 69—101) (Mohs hardness ∼3—3½). In reflected light, dalnegroite is highly bireflectant and weakly pleochroic, from white to a slightly greenish-grey. In cross-polarized light, it is highly anisotropic with bluish to green rotation tints and red internal reflections.According to chemical and X-ray diffraction data, dalnegroite appears to be isotypic with chabournéite, Tl5-xPb2x(Sb,As)21-xS34. It is triclinic, probable space groupP1, witha= 16.217(7) Å,b= 42.544(9) Å,c= 8.557(4) Å, α = 95.72(4)°, β = 90.25(4)°, γ = 96.78(4)°,V= 5832(4) Å3,Z= 4.The nine strongest powder-diffraction lines [d(Å) (I/I0) (hkl)] are: 3.927 (100) (10 0); 3.775 (45) (22); 3.685 (45) (60); 3.620 (50) (440); 3.124 (50) (2); 2.929 (60) (42); 2.850 (70) (42); 2.579 (45) (02); 2.097 (60) (024). The mean of 11 electron microprobe analyses gave elemental concentrations as follows: Pb 10.09(1) wt.%, Tl 20.36(1), Sb 23.95(1), As 21.33(8), S 26.16(8), totalling 101.95 wt.%, corresponding to Tl4.15Pb2.03(As11.86Sb8.20)S34. The new mineral is named for Alberto Dal Negro, Professor in Mineralogy and Crystallography at the University of Padova since 1976.

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LIMANOVA, SVETLANA. "FERSMAN’S LIFE IN THE LIGHT OF GEMS (BY DOCUMENTS FROM THE ARCHIVE OF THE RUSSIAN ACADEMY OF SCIENCES)." LIFE OF THE EARTH 42, no. 3 (August 26, 2020): 304–12. http://dx.doi.org/10.29003/m1484.0514-7468.2020_42_3/304-312.

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The article presents the most important stages of Fersman’s biography. Alexander Evgenievich Fersman was a recognized expert in mineralogy, crystallography and geochemistry. In 1919, at the age of 35, Fersman became an academician of the Academy of Sciences. From 1926 to 1929 he was a vice-president of the USSR Academy of Sciences. Fersman’s personal fund is kept in the Archive of the Russian Academy of Sciences. Life choices and the fi professional success are shown on the basis of documents from the personal fund. Fersman crossed the path from a youthful interest in gems (morphology, structure, chemical composition) to the realization of his scientifi potential as the head of the major research projects. Fersman was awarded the Lenin Prize (1929), USSR State Prize (1942), Order of the Red Banner of Labour (1943) and Wollaston Medal of the Geological Society of London (1943). Particular attention is paid to the work of A.E. Fersman's assessment and attribution of precious stones from the Diamond Fund. Fersman led a special commission and carried out the mission with great enthusiasm. Having studied physicochemical properties of stones he provided the necessary information and reports. Also, he studied the historical and cultural context of jewelry making. Aft the commission completed its work, Fersman had a variety of documents on the history of gems. A.E. Fersman was pleased to share the results of his work. He was actively engaged in the popularization of scientifi knowledge. His books reveal the amazing world of gems and enable an examination of the evolution of the scientist's views. In addition to biographical information, unique visual documents are presented. Th are papers and photographs from the Fersman’s personal fund.

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Krivovichev, Sergey V. "Polyoxometalate clusters in minerals: review and complexity analysis." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 76, no. 4 (July 14, 2020): 618–29. http://dx.doi.org/10.1107/s2052520620007131.

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Most research on polyoxometalates (POMs) has been devoted to synthetic compounds. However, recent mineralogical discoveries of POMs in mineral structures demonstrate their importance in geochemical systems. In total, 15 different types of POM nanoscale-size clusters in minerals are described herein, which occur in 42 different mineral species. The topological diversity of POM clusters in minerals is rather restricted compared to the multitude of moieties reported for synthetic compounds, but the lists of synthetic and natural POMs do not overlap completely. The metal–oxo clusters in the crystal structures of the vanarsite-group minerals ([As3+V4+ 2V5+ 10As5+ 6O51]7−), bouazzerite and whitecapsite ([M 3+ 3Fe7(AsO4)9O8–;n (OH) n ]), putnisite ([Cr3+ 8(OH)16(CO3)8]8−), and ewingite ([(UO2)24(CO3)30O4(OH)12(H2O)8]32−) contain metal–oxo clusters that have no close chemical or topological analogues in synthetic chemistry. The interesting feature of the POM cluster topologies in minerals is the presence of unusual coordination of metal atoms enforced by the topological restraints imposed upon the cluster geometry (the cubic coordination of Fe3+ and Ti4+ ions in arsmirandite and lehmannite, respectively, and the trigonal prismatic coordination of Fe3+ in bouazzerite and whitecapsite). Complexity analysis indicates that ewingite and morrisonite are the first and the second most structurally complex minerals known so far. The formation of nanoscale clusters can be viewed as one of the leading mechanisms of generating structural complexity in both minerals and synthetic inorganic crystalline compounds. The discovery of POM minerals is one of the specific landmarks of descriptive mineralogy and mineralogical crystallography of our time.

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Filatov, Stanislav K., Andrey P. Shablinskii, Sergey V. Krivovichev, Lidiya P. Vergasova, and Svetlana V. Moskaleva. "Petrovite, Na10CaCu2(SO4)8, a new fumarolic sulfate from the Great Tolbachik fissure eruption, Kamchatka Peninsula, Russia." Mineralogical Magazine 84, no. 5 (June 30, 2020): 691–98. http://dx.doi.org/10.1180/mgm.2020.53.

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AbstractPetrovite, Na10CaCu2(SO4)8, is a new sulfate mineral discovered on the Second scoria cone of the Great Tolbachik fissure eruption. The mineral occurs as globular aggregates of tabular crystals up to 0.2 mm in maximal dimension, generally with gaseous inclusions. The empirical formula calculated on the basis of O = 32 is Na6(Na1.80K0.20)Σ2Na(Ca0.82Na0.06Mg0.02)Σ0.90(Cu1.84Mg0.16)Σ2(Na0.52□0.48)Σ1S8.12O32. The crystal-chemical formula is CuNa6−2xCax(SO4)4, which, for x ≈ 0.5, results in the idealised formula Na10CaCu2(SO4)8. The crystal structure of petrovite was determined using single-crystal X-ray diffraction data; the space group is P21/c, a = 12.6346(8), b = 9.0760(6), c = 12.7560(8) Å, β = 108.75(9)°, V = 1385.1(3) Å3, Z = 2 and R1 = 0.051. There are one Cu and six Na sites, one of which is also occupied by the essential amount of Ca. The Cu atom forms five Cu–O bonds in the range 1.980–2.180 Å and two long bonds ≈ 2.9 Å resulting in the formation of the CuO7 polyhedra, which share corners with SO4 tetrahedra to form isolated [Cu2(SO4)8]12− clusters. The clusters are surrounded by Na sites, which provide their linkage into a three-dimensional framework. The Mohs’ hardness is 4. The mineral is biaxial (+), with α = 1.498(3), βcalc = 1.500, γ = 1.516(3) and 2V = 20(10) (λ = 589 nm). The seven strongest lines of the powder X-ray diffraction pattern [d, Å (I, %) (hkl)] are: 7.21(27)(110); 6.25(38)(102); 4.47(31)(212); 3.95(21)(30$\bar{2}$); 3.85(17)(121); 3.70(36)(202); and 3.65(34)(22$\bar{1}$). The mineral is named in honour of Prof Dr Tomas Georgievich Petrov (b. 1931) for his contributions to mineralogy and crystallography and, in particular, for the development of technology for the industrial fabrication of jewellery malachite.

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Bindi, L., C. Carbone, R. Cabella, and G. Lucchetti. "Bassoite, SrV3O7·4H2O, a new mineral from Molinello mine, Val Graveglia, eastern Liguria, Italy." Mineralogical Magazine 75, no. 5 (October 2011): 2677–86. http://dx.doi.org/10.1180/minmag.2011.075.5.2677.

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AbstractBassoite, ideally SrV3O7·4H2O, is a new mineral from the Molinello manganese mine, Val Graveglia. eastern Liguria, northern Apennines, Italy. It occurs as black euhedral to subhedral grains up to 400 urn across, closely associated with rhodonite, quartz and braunite. Bassoite is opaque with a sub-metallic lustre and a black streak. It is brittle and neither fracture nor cleavage was observed; the Vickers micro-hardness (VHN100) is 150 kg/mm (range 142—165; corresponding to a Mohs hardness of 4—41/2). The calculated density is 2.940 g/cm3 (on the basis of the empirical formula and X-ray single-crystal data). Bassoite is weakly bireflectant and very weakly pleochroic from grey to a dark green. Internal reflections are absent. The mineral is anisotropic, without characteristic rotation tints. Reflectance percentages (Rmin and Rmax) for the four standard COM wavelengths are 18.5%, 19.0% (471.1 nm); 17.2%, 17.8% (548.3 nm); 16.8%, 17.5% (586.6 nm) and 16.2%, 16.8% (652.3 nm), respectively.Bassoite is monoclinic, space group P21/m, with unit-cell parameters: a = 5.313(3) Å, b = 10.495(3) Å, c = 8.568(4) Å, β = 91.14(5)°, V= 477.7(4) Å3, a:b:c = 0.506:1:0.816, and Z = 2. The crystal structure was refined to R1 = 0.0209 for 1148 reflections with Fo > 4σ(Fo) and it consists of layers of VO5 pyramids (with vanadium in the tetravalent state) pointing up and down alternately with Sr between the layers (in nine-fold coordination). The nine most intense X-ray powder-diffraction lines [d in Å (I/I0) (hkt)] are: 8.5663 (100) (001); 6.6363 (14) (011); 3.4399 (14) (1̄21); 3.4049 (17) (121); 2.8339 (15) (1̄22); 2.7949 (11) (122); 2.6550 (15) (200); 2.6237 (11) (040) and 1.8666 (15) (240). Electron microprobe analyses produce a chemical formula (Sr0.97Ca0.02Na0.01)V3.00O74H20, on the basis of 2(Sr+Ca+Na) = 1, taking the results of the structure refinement into account. The presence of water molecules was confirmed by micro-Raman spectroscopy. The name honours Riccardo Basso (b. 1947), full professor of Mineralogy and Crystallography at the University of Genova. The new mineral and mineral name have been approved by the Commission on New Minerals, Nomenclature and Classification, IMA (2011-028).

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Pattrick, R. A. D. "C.N. Alpers, J.L. Jambor and D.K. Nordstrom (Eds) Sulfate Minerals: Crystallography, Geochemistry and Environmental Significance. Washington, D.C. (Mineralogical Society of America, Reviews in Mineralogy and Geochemistry, 40). 2000, xiv + 608 pp. Price $32. ISBN 0 939950 52 9." Mineralogical Magazine 65, no. 6 (December 2001): 817–18. http://dx.doi.org/10.1180/s0026461x0003992x.

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Sokolova, E., Y. Abdu, F. C. Hawthorne, A. V. Stepanov, G. K. Bekenova, and P. E. Kotel’nikov. "Cámaraite, Ba3NaTi4(Fe2+,Mn)8(Si2O7)4O4(OH,F)7. I. A new Ti-silicate mineral from the Verkhnee Espe Deposit, Akjailyautas Mountains, Kazakhstan." Mineralogical Magazine 73, no. 5 (October 2009): 847–54. http://dx.doi.org/10.1180/minmag.2009.073.5.847.

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AbstractCámaraite, ideally Ba3NaTi4(Fe2+,Mn)8(Si2O7)4O4(OH,F)7, is a new mineral from the Verkhnee Espe deposit, Akjailyautas Mountains, Kazakhstan. It occurs as intergrowths with bafertisite and jinshajiangite in separate platy crystals up to 8 mm × 15 mm × 2 mm in size, or as star-shaped aggregates of crystals with different orientations. Individual crystals are orange-red to brownish-red, and are platy on {001}. Cámaraite is translucent and has a pale-yellow streak, a vitreous lustre, and does not fluoresce under cathode or ultraviolet light. Cleavage is {001} perfect, no parting was observed, and Mohs hardness is <5; the mineral is brittle. The calculated density is 4.018 g cm-3. In transmitted light, camaraite is strongly pleochroic, X = light brown, Y = reddish-brown, Z = yellow- brown, with Z < X < Y. Cámaraite is biaxial +ve and 2Vmeas. = 93(1)°. All refractive indices are greater than 1.80. Cámaraite is triclinic, space group C, a = 10.678(4) Å, b = 13.744(8) Å, c = 21.40(2) Å, α = 99.28(8)°, β = 92.38(5)°, γ = 90.00(6)°, V = 3096(3) Å3, Z = 4, a:b:c = 0.7761:1:1.5565. The seven strongest lines in the X-ray powder-diffraction pattern are as follows: [d (Å), (I), (hkl)]: 2.63, (100), (401); 2.79, (90), (3, 41, 26, 225); 1.721, (70), (11, 49, 02); 3.39, (50), (24, 223); 3.18, (50), (5, 24); 2.101, (50), (2, 40); 1.578, (50), (1, 2, 61, 40). Chemical analysis by electron microprobe gave: Nb2O5 1.57, SiO2 25.25, TiO2 15.69, ZrO2 0.33, Al2O3 0.13, Fe2O3 2.77, FeO 16.54, MnO 9.46, ZnO 0.12, MgO 0.21, CaO 0.56, BaO 21.11, Na2O 1.41, K2O 0.84, H2O 1.84, F 3.11, less O:F 1.31, total 99.63 wt.%, where the valence state of Fe was determined by Mössbauer spectroscopy [Fe3+/(Fe2+ + Fe3+) = 0.13(8)] and the H2O content was derived by crystal-structure determination. The resulting empirical formula on the basis of 39 anions is Ca0.05)Σ7.78Si7.97O35.89H3.88F3.11. Cámaraite is a Group-II TS-block mineral in the structure hierarchy of Sokolova (2006). The mineral is named camaraite after Fernando Cámaraite (born 1967) of Melilla, Spain, in recognition of his contribution to the fields of mineralogy and crystallography. The new mineral and mineral name have been approved by the Commission on New Minerals, Nomenclature and Classification, International Mineralogical Association (IMA 2009-11).

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Cámara, F., F. Nestola, L. Bindi, A. Guastoni, F. Zorzi, L. Peruzzo, and D. Pedron. "Tazzoliite: a new mineral with a pyrochlore-related structure from the Euganei Hills, Padova, Italy." Mineralogical Magazine 76, no. 4 (August 2012): 827–38. http://dx.doi.org/10.1180/minmag.2012.076.4.01.

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AbstractTazzoliite, ideally Ba2CaSr0.5Na0.5Ti2Nb3SiO17[PO2(OH)2]0.5, is a new mineral (IMA 2011-018) from Monte delle Basse, Euganei Hills, Galzignano Terme, Padova, Italy. It occurs as lamellar pale orange crystals, which are typically a few m m thick and up to 0.4 mm long, closely associated with a diopsidic pyroxene and titanite. Tazzoliite is transparent. It has a white streak, a pearly lustre, is not fluorescent and has a hardness of 6 (Mohs' scale). The tenacity is brittle and the crystals have a perfect cleavage along {010}. The calculated density is 4.517 g cm–3. Tazzoliite is biaxial (–) with 2Vmeas of ~50º, it is not pleochroic and the average refractive index is 2.04. No twinning was observed. Electronmicroprobe analyses gave the following chemical formula: (Ba1.93Ca1.20Sr0.52Na0.25Fe0.102+)Σ4 (Nb2.88Ti2.05Ta0.07Zr0.01V0.015+)Σ5.02SiO17[(P0.13Si0.12S0.07)Σ0.32O0.66(OH)0.66][F0.09(OH)0.23]Σ0.32.Tazzoliite is orthorhombic, space group Fmmm, with unit-cell parameters a = 7.4116(3), b = 20.0632(8), c = 21.4402(8) Å, V = 3188.2(2) Å3 and Z = 8. The crystal structure, obtained from single-crystal X-ray diffraction data, was refined to R1(F2) = 0.063. It consists of a framework of Nb(Ti) octahedra and BaO7 polyhedra sharing apexes or edges, and Si tetrahedra sharing apexes with Nb(Ti) octahedra and BaO7 polyhedra. The structure, which is related to the pyrochlore structure, contains three Nb(Ti) octahedra: two are Nb dominant and one is Ti dominant. Chains of A2O8 polyhedra [A2 being occupied by Sr(Ca, Fe)] extend along [100] and are surrounded by Nb octahedra. Channels formed by six Nb(Ti) octahedra and two tetrahedra, or four A1O8(OH) polyhedra (A1 being occupied by Ba), alternate along [100]. The channels are partially occupied by [PO2(OH)2] in two possible mutually exclusive positions, alternating with fully occupied A3O7 polyhedral pairs [A3 being occupied by Ca(Na)]. The seven strongest X-ray powder diffraction lines [d in Å (I/I0) (hkl)] are: 3.66 (60) (044), 3.16 (30) (153), 3.05 (100) (204), 2.98 (25) (240), 2.84 (50) (064), 1.85 (25) (400) and 1.82 (25) (268). Raman spectra of tazzoliite were collected in the range 150–3700 cm–1 and confirm the presence of OH groups. Tazzoliite is named in honour of Vittorio Tazzoli in recognition of his contributions to the fields of mineralogy and crystallography.

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Braun, Jean-Jacques, Bernard Dupré, Jérôme Viers, Jules Rémy Ndam Ngoupayou, Jean-Pierre Bedimo Bedimo, Luc Sigha-Nkamdjou, Rémi Freydier, et al. "Biogeohydrodynamic in the forested humid tropical environment: the case study of the Nsimi small experimental watershed (south Cameroon)." Bulletin de la Société Géologique de France 173, no. 4 (July 1, 2002): 347–57. http://dx.doi.org/10.2113/173.4.347.

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Abstract This paper summarizes a six-year study of the Nsimi Small Experimental Watershed (SEW), considered as a model for the South Cameroon humid tropical ecosystem. When this small watershed was set up, no similar survey of input/output hydrobiogeochemical fluxes in granitoid rocks in stable cratonic environment was available, to our knowledge, on any site close to the Equator. Moreover, this is the first attempt, world-wide, to combine different approaches in hydrology, (bio)geochemistry, mineralogy, crystallography, microbiology, geophysics and pedology. Research is based on (1) regular hydrobiogeochemical surveys in various water reservoirs of the SEW ecosystem (atmospheric deposits, groundwater and stream), (2) surveys related either to the organisation and composition of different reservoirs in the superficial layers (basement rocks, saprolite, soils) or to various hydrological, biological and geochemical processes. These surveys aim at (1) finding the main parameters involved in the chemical and physical erosion processes of the humid tropical ecosystem, (2) understanding the source of a particular chemical composition in groundwater and rivers, (3) documenting accurately the different exportation processes of chemical elements in water and soil (4) investigating the possible relation between the biodegradation of soil organic matter and the leaching of metals (especially iron) and (5) comparing the long and short term weathering rates using mass balance calculations. Another important objective of this study is to provide a new scientific and engineering database for the future development of South Cameroon, which is still nowadays a relatively preserved ecosystem. One of the major results is the essential role played by the biological cycle (vegetation and soil organic matter) in the fractionation, exportation or storage of the chemical elements in humid tropical environments. Moreover we are able to propose a model of the current erosion for this SEW from the database obtained on (1) the mineralogy of the basement rocks and the soil layers, (2) the geochemistry of the soluble and colloidal phases of waters and (3) the hydrology within the different reservoirs of the hydrosystem. This model has been confirmed and extended on a regional scale (Nyong river basin). It emphasized the behaviour of the main elements of the tropical soil layers (Fe, Al, Si), the nutrients (C, Ca, Mg, K, Sr) and specific tracers of the weathering processes either with strong mobility (Cl, Na) or on the contrary with an extremely low mobility (Zr, Th, REEs). On the SEW scale, a strong geochemical contrast occurs between the different groundwater zones flooding (1) the hill slope lateritic profiles, (2) the weathering front (interface between the saprolite and the basement rocks), and (3) the swampy zone in which the Mengong brook flows. High DOC contents (15 mg/L) but also high Fe, Th, Al, Zr contents characterize the swampy zone waters. Na and Si have mainly a deep origin (exfiltration), Al, Th, Zr and REEs are strongly linked with colloidal organic matter located in the upper horizons of the swamp. Fe has a much more complex behaviour due to its change of redox state which can be independent of organic matter complexation. Concerning the major base cations, their origin can be constrained by the biological cycle (storage or leaching). K is typically influenced by the biological cycle. During the floods, Cl has the same behaviour as K: it is one of the most striking points of this study. However, the Cl annual budget is balanced. These characteristics can be understood as the consequence of the weathering of the minerals present in the saprolite (kaolinite, goethite, zircon, Th-oxide). This chemical weathering allows the leaching of base cations and also Al and Fe. It has been demonstrated that the microbial populations of the swampy zone can play an important role in the mobilization of transition metals (e.g. Fe). This study point out the role of humic acids in the transport and the weathering budget of elements usually considered as immobile in the superficial cycle (e.g. Al, Th, Zr, Fe). It must be mentioned that worldwide the SEW and even the Nyong network waters are among the least concentrated river waters. It means that even if the organic matter plays an important role in the mobilization and transport of some elements in the swampy zone, its action is limited in term of major cation fluxes on the SEW scale. The reason invoked is that the cation fluxes are directly linked to the pedological history and the geomorphology of the watershed. The presence of thick soil layers composed of saprolite and latosol on the hillsides and of hydromorphic soils in the swampy zone with constant mineralogy lead to isolating the bedrock. The long residence time of water close to the weathering front plays a major role in preserving the parent rock from the hydro-chemical outputs. Moreover, the topsoil layers are stabilized by the vegetation cover, which limits mechanical erosion. This should be taken into account for the carbon mass balance calculation because of the wide areas on stable shields concerned by the humid tropical ecosystems. Moreover, comparison between long and short-term weathering allows us to suggest that paleo-climatic conditions did not change since the Miocene (6–20 Ma) in this part of the world.

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Cámara, F., E. Sokolova, F. C. Hawthorne, R. Rowe, J. D. Grice, and K. T. Tait. "Veblenite, K2☐2Na(Fe2+5Fe3+4Mn2+7☐)Nb3Ti(Si2O7)2(Si8O22)2O6(OH)10(H2O)3, a new mineral from Seal Lake, Newfoundland and Labrador: mineral description, crystal structure, and a new veblenite Si8O22 ribbon." Mineralogical Magazine 77, no. 7 (October 2013): 2955–74. http://dx.doi.org/10.1180/minmag.2013.077.7.06.

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AbstractVeblenite, ideally K2☐2Na(Fe2+5Fe3+4Mn2+7☐)Nb3Ti(Si2O7)2(Si8O22)2O6(OH)10(H2O)3, is a new mineral with no natural or synthetic analogues. The mineral occurs at Ten Mile Lake, Seal Lake area, Newfoundland and Labrador (Canada), in a band of paragneiss consisting chiefly of albite and arfvedsonite. Veblenite occurs as red brown single laths and fibres included in feldspar. Associated minerals are niobophyllite, albite, arfvedsonite, aegirine-augite, barylite, eudidymite, neptunite, Mn-rich pectolite, pyrochlore, sphalerite and galena. Veblenite has perfect cleavage on {001} and splintery fracture. Its calculated density is 3.046 g cm–3. Veblenite is biaxial negative with α 1.676(2), β 1.688(2), γ 1.692(2) (λ 590 nm), 2Vmeas = 65(1)°, 2Vcalc = 59.6°, with no discernible dispersion. It is pleochroic in the following pattern: X = black, Y = black, Z = orange-brown. The mineral is red-brown with a vitreous, translucent lustre and very pale brown streak. It does not fluoresce under short and long-wave UV-light. Veblenite is triclicnic, space group P, a 5.3761(3), b 27.5062(11), c 18.6972(9) Å, α 140.301(3), β 93.033(3), γ 95.664(3)°, V = 1720.96(14) Å3. The strongest lines in the X-ray powder diffraction pattern [d(Å)(I)(hkl)] are: 16.894(100)(010), 18.204(23)(01), 4.271(9)(, 040, 120), 11.661(8)(001), 2.721(3)(), 4.404(3)(, ), 4.056(3)(031, 12; , ), 3.891(2)(003).The chemical composition of veblenite from a combination of electron microprobe analysis and structural determination for H2O and the Fe2+/Fe3+ ratio is Nb2O5 11.69, TiO2 2.26, SiO2 35.71, Al2O3 0.60, Fe2O3 10.40, FeO 11.58, MnO 12.84, ZnO 0.36, MgO 0.08, BaO 1.31, SrO 0.09, CaO 1.49, Cs2O 0.30, K2O 1.78, Na2O 0.68, H2O 4.39, F 0.22, O = F –0.09, sum 95.69 wt.%. The empirical formula [based on 20 (Al+Si) p. f. u. is (K0.53Ba0.28Sr0.03☐0.16)Σ1(K0.72Cs0.07☐1.21)Σ2(Na0.72Ca0.17☐1.11)Σ2(Fe2+5.32Fe3+4.13Mn2+5.97Ca0.70Zn0.15Mg0.07☐0.66)Σ17(Nb2.90Ti0.93Fe3+0.17)Σ4(Si19.61Al0.39)Σ20O77.01H16.08F0.38. The simplified formula is (K, Ba, ☐)3(☐, Na)2(Fe2+, Fe3+, Mn2+)17(Nb,Ti)4(Si2O7)2(Si8O22)2O6(OH)10(H2O)3. The infrared spectrum of the mineral contains the following bands (cm–1): 453, 531, 550, 654 and 958, with shoulders at 1070, 1031 and 908. A broad absorption was observed between ~3610 and 3300 with a maximum at ~3525. The crystal structure was solved by direct methods and refined to an R1 index of 9.1%. In veblenite, the main structural unit is an HOH layer, which consists of the octahedral (O) and two heteropolyhedral (H) sheets. The H sheet is composed of Si2O7 groups, veblenite Si8O22 ribbons and Nb-dominant D octahedra. This is the first occurrence of an eight-membered Si8O22 ribbon in a mineral crystal structure. In the O sheet, (Fe2+, Fe3+, Mn2+) octahedra share common edges to form a modulated O sheet parallel to (001). HOH layers connect via common vertices of D octahedra and cations at the interstitial A(1,2) and B sites. In the intermediate space between two adjacent HOH layers, the A(1) site is occupied mainly by K; the A(2) site is partly occupied by K and H2O groups, the B site is partly occupied by Na. The crystal structure of veblenite is related to several HOH structures: jinshanjiangite, niobophyllite (astrophyllite group) and nafertisite. The mineral is named in honour of David R. Veblen in recognition of his outstanding contributions to the fields of mineralogy and crystallography.

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Birkett, T. "Sulfate Minerals: Crystallography, Geochemistry, and Environmental Significance.: C.N. Alpers, J.L. Jambor and D.K. Nordstrom, editors. Reviews in Mineralogy and Geochemistry, volume 40, Short Course, Mineralogical Society of America, Washington, D.C., U.S.A. and The Geochemical Society, St. Louis, Missouri, U.S.A. 608 pages. Price US$32 for non-members, US$24 for members. ISBN 0 939950 52 9." Canadian Mineralogist 39, no. 6 (December 1, 2001): 1749–50. http://dx.doi.org/10.2113/gscanmin.39.6.1749.

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"Crystallography and mineralogy." Zeitschrift für Kristallographie - Crystalline Materials 185, no. 1-6 (January 1, 1988). http://dx.doi.org/10.1524/zkri.1988.185.jg.595.

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"Science Academies’ Refresher Course on crystallography, mineralogy, igneous petrology and thermodynamics." Resonance 19, no. 9 (September 2014): 874. http://dx.doi.org/10.1007/s12045-014-0098-7.

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