https://ejm.copernicus.org/articles/ Recent articles of the journal European Journal of Mineralogy https://doi.org/10.5194/ejm-38-325-2026 <b>Argentotennantite-(Fe), Ag6(Cu4Fe2)As4S13, a new member of the tetrahedrite group from the San Genaro mine, Peru: occurrence and crystal structure</b><br> Jiří Sejkora, Dalibor Velebil, Cristian Biagioni, Zdeněk Dolníček, and Jaroslav Hyršl<br> Eur. J. Mineral., 38, 325–336, https://doi.org/10.5194/ejm-38-325-2026, 2026<br> Argentotennantite-(Fe), ideally Ag6(Cu4Fe2)As4S13, is a new member of the tetrahedrite group found in the San Genaro mine, Castrovirreyna Province, Huancavelica, Peru. It occurs as anhedral grains up to 100 μm in size, or, more commonly, it forms micrometer-sized rims around crystals of argentotetrahedrite-(Zn) or replaces the latter around cavities and fissures, along with Ag-rich tennantite-(Fe). It is cubic, I3m, with a = 10.4365(5) Å, V = 1136.75(17) Å3. 2026-06-11T16:48:42+02:00 https://doi.org/10.5194/ejm-38-305-2026 <b>Formation of black opal in the pegmatites from Volyn (Ukraine) – an example for interaction of silica with organic matter</b><br> Gerhard Franz, Vladimir Khomenko, Vsevolod Chornousenko, Armin Zeh, Ferry Schiperski, Simon Gouzy, Ulrich Gernert, and Jörg Nissen<br> Eur. J. Mineral., 38, 305–324, https://doi.org/10.5194/ejm-38-305-2026, 2026<br> Black opal, a rare amorphous SiO2 variety, results from the interaction of silica with organic matter and therefore hints at traces of life, including the early Earth and Mars. The Volyn occurrence is one of the few examples of black opal worldwide and is the unique case of a pegmatitic occurrence in a granite; its age is at least 200 Ma. The structure consists of micrometer-large sphere-like arrangements of nano-sized grains and shows shape relicts of fossils, known from Volyn as "kerite". 2026-05-22T16:48:42+02:00 https://doi.org/10.5194/ejm-38-281-2026 <b>Mineralogy of sulfide mineralization from the world-class Li–Sn–W Cínovec greisen-type deposit, Bohemian Massif, Czech Republic</b><br> Ondřej Krátký, Jan Cempírek, Sebastián Hreus, Luboš Vrtiška, Jiří Sejkora, Zdeněk Dolníček, Jakub Výravský, Radek Škoda, Karel Breiter, and Vojtěch Šešulka<br> Eur. J. Mineral., 38, 281–304, https://doi.org/10.5194/ejm-38-281-2026, 2026<br> Mineralogical, paragenetic, and geochemical data on sulfidic mineralization from the Cínovec greisen-type deposit show that distribution of sulfides is irregular and not strictly bound to prevalent Li–Sn–W mineralization. Progressive development of metal contents in the reduced sulfide-bearing hydrothermal fluid proceeds from Zn–Cu–Sn to Pb–Bi–Ag and As–Sb. Late-stage sulfate- and fluorine-bearing fluids partly altered earlier mineralization but did not deposit significant ore content. 2026-05-20T16:48:42+02:00 https://doi.org/10.5194/ejm-38-263-2026 <b>Retrograde crystallization of clay minerals in metamorphic rocks linked to fluid circulation related to fault activity</b><br> Isabel Abad, Matías Reolid, Juan Jiménez-Millán, and Fernando Nieto<br> Eur. J. Mineral., 38, 263–280, https://doi.org/10.5194/ejm-38-263-2026, 2026<br> Metamorphic rocks affected by a fault have undergone chemical, mineralogical, and textural changes. The most significant is the enrichment in clay minerals (chlorite, kaolinite, and smectite). Geothermometry of the new chlorites made it possible to determine the temperatures of the processes (predominantly < 225°C), promoted by the fault dynamics (mainly fluid-related alterations). The retrograde alteration also affected the fluid-accessible zones of the original rocks, with growth of the same clay minerals. 2026-05-11T16:48:42+02:00 https://doi.org/10.5194/ejm-38-249-2026 <b>The Tibet leucogranite as a potential high-purity-quartz raw material: first discovery and case study from the Dinggye area</b><br> Liting Sun, Xiaoyong Yang, Mei Xia, Yue Qiu, Zhenhui Hou, Xiaohu Fu, and Zetai Chen<br> Eur. J. Mineral., 38, 249–262, https://doi.org/10.5194/ejm-38-249-2026, 2026<br> This study evaluates leucogranites from the Ama Drime Massif, Dinggye, Tibet, as a potential raw material for high-purity quartz. Petrographic, geochemical, and purification analyses of two representative samples show that the rocks are mainly composed of quartz, albite, and K-feldspar. After purification, the quartz reached SiO₂ contents of 99.996 % and 99.995 %, indicating promising potential as a supplementary high-purity-quartz resource. 2026-04-30T16:48:42+02:00 https://doi.org/10.5194/ejm-38-237-2026 <b>Erzwiesite, Ag8Pb12Bi16S40, the natural orthorhombic N =  8 member of the lillianite homologous series</b><br> Dan Topa, Emil Makovicky, Hubert Putz, Werner Hermann Paar, and Georg Zagler<br> Eur. J. Mineral., 38, 237–247, https://doi.org/10.5194/ejm-38-237-2026, 2026<br> Erzwiesite, ideally Ag8Pb12Bi16S40, Z = 1, is a new sulfosalt mineral discovered in the Erzwies mining area, Gastein Valley, Salzburg Province, Austria. The empirical formula is (Ag,Cu)8.23(Pb,Cd)11.33(Bi,Sb)16.31 (S,Te,Se)40.03 (based on 76 apfu). Erzwiesite crystallises in space group Cmcm (a = 4.085(5), b = 13.462(15), c = 33.92(4) Å, and V = 1866(4) ų). Erzwiesite is the first natural (8:8) homologue of the lillianite homologous series and is named after its type locality. 2026-04-29T16:48:42+02:00 https://doi.org/10.5194/ejm-38-231-2026 <b>IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) – Newsletter 90</b><br> Ferdinando Bosi, Frédéric Hatert, Marco Pasero, and Stuart J. Mills<br> Eur. J. Mineral., 38, 231–235, https://doi.org/10.5194/ejm-38-231-2026, 2026<br> There is no short summary. 2026-04-28T16:48:42+02:00 https://doi.org/10.5194/ejm-38-209-2026 <b>Plumbogottlobite, PbMg(VO4)(OH), the Pb analogue of gottlobite and the Mg analogue of descloizite</b><br> Anthony R. Kampf, Joy Désor, and Chi Ma<br> Eur. J. Mineral., 38, 209–216, https://doi.org/10.5194/ejm-38-209-2026, 2026<br> This paper describes the new mineral plumbogottlobite from the Glücksstern mine, Gottlob Hill, Friedrichroda, Gotha District, Thuringia, Germany. It occurs as thick, square, orange-brown, tabular crystals up to about 0.2 mm in diameter. The mineral is the lead (Pb) analogue of the mineral gottlobite, which occurs at the same locality and is identical in appearance. Plumbogottlobite is a late-stage, low-temperature hydrothermal mineral occurring on baryte and hausmannite. 2026-04-23T16:48:42+02:00 https://doi.org/10.5194/ejm-38-217-2026 <b>Lopatkaite, a new mineral from Taylor Pit, Madoc, Ontario, Canada</b><br> Dan Topa, Emil Makovicky, Hubert Putz, and Georg Zagler<br> Eur. J. Mineral., 38, 217–229, https://doi.org/10.5194/ejm-38-217-2026, 2026<br> Lopatkaite, ideally Pb10As2Sb6S22 (Z = 4), is a new arsenic-bearing sulfosalt species found in the Madoc deposit, Taylor Pit, Ontario, Canada. Associated minerals in the holotype specimen are boulangerite, veenite, and sterryite, all embedded in a calcite matrix. The ideal formula may be derived from the ideal boulangerite formula, Pb10Sb8S22 (Z = 4), by a substitution of 2Sb with 2As. Lopatkaite is a homeotype of boulangerite and a new member of the rod-based family of sulfosalts.  2026-04-23T16:48:42+02:00 https://doi.org/10.5194/ejm-38-197-2026 <b>Selective uptake of rare earth elements and other cations in sector-zoned natural calcite as analogues for trivalent actinide behavior </b><br> Ferdinand Baumeister, Martin Kutzschbach, Martina Klinkenberg, Felix Brandt, and Thomas Neumann<br> Eur. J. Mineral., 38, 197–208, https://doi.org/10.5194/ejm-38-197-2026, 2026<br> This study shows that calcite can trap elements similar to radioactive substances very effectively under natural conditions. By studying a sample formed under nuclear-waste-repository-like conditions, it was found that certain crystal parts hold over 200 times more of these elements. This happens through multiple processes, helping to safely store harmful substances even in low-salt environments, which is important for nuclear waste safety. 2026-04-20T16:48:42+02:00 https://doi.org/10.5194/ejm-38-179-2026 <b>Hydrous partial melting in gabbros drilled at the Southwest Indian Ridge (ODP Hole 735B): evidence from microstructures at grain boundaries</b><br> Jürgen Koepke<br> Eur. J. Mineral., 38, 179–195, https://doi.org/10.5194/ejm-38-179-2026, 2026<br> Gabbroic rocks from the Southwest Indian Ridge have been investigated. The results show that hydrous partial melting triggered by hydrothermal fluids percolating on grain boundaries above the wet gabbro solidus is a common process at slow-spreading mid-ocean ridges. The main indication of this process is plagioclase strongly enriched in anorthite content at grain boundaries, which can only be identified via backscattered electron imaging and related electron microprobe profiles. 2026-04-09T16:48:42+02:00 https://doi.org/10.5194/ejm-38-169-2026 <b>Friisite, Pb8Al3Si8O27Cl3, a new mineral with a polysomatic relation to jagoite, from Långban, Sweden</b><br> Dan Holtstam, Fernando Cámara, and Andreas Karlsson<br> Eur. J. Mineral., 38, 169–177, https://doi.org/10.5194/ejm-38-169-2026, 2026<br> Friisite is a newly identified mineral, with the chemical formula Pb8Al3Si8O27Cl3, from the Långban mine in Sweden, found as tiny, white, flaky grains within a skarn matrix alongside jagoite and other silicates. It has a sub-adamantine luster, perfect basal cleavage, a hardness of 4–5, and a high density of 5.54 g cm−³. Structurally it is a hexagonal phyllosilicate, closely related to jagoite in a polysomatic series. The mineral is named in honor of Danish mineralogist Henrik Friis. 2026-04-02T16:48:42+02:00 https://doi.org/10.5194/ejm-38-153-2026 <b>When mineralogy meets the organic chemistry: delchiaroite, Cu3I(CH3S)2, the first copper iodide–methanethiolate from the Carrara marble quarries, Apuan Alps, Tuscany, Italy</b><br> Cristian Biagioni, Jiří Sejkora, Yves Moëlo, Antonino Criscuolo, and Zdeněk Dolníček<br> Eur. J. Mineral., 38, 153–167, https://doi.org/10.5194/ejm-38-153-2026, 2026<br> Delchiaroite is the first iodide–methanethiolate mineral and represents an interesting example where organic chemistry meets mineralogy. 2026-04-01T16:48:42+02:00 https://doi.org/10.5194/ejm-38-135-2026 <b>Mackinawite transformation into greigite at room temperature under anoxic and acidic conditions: a corrosion pathway?</b><br> Pierre Le Pape, Benoît Baptiste, Guillaume Radtke, Delphine Cabaret, Julie Aufort, Jessica Brest, Camille Baya, Erik Elkaim, Georges Ona-Nguema, Farid Juillot, and Guillaume Morin<br> Eur. J. Mineral., 38, 135–152, https://doi.org/10.5194/ejm-38-135-2026, 2026<br> Iron sulfides are ubiquitous minerals of sedimentary environments. Several research works consider it to be that they preserve evidence of their original deposition environment, allowing us to derive paleo-environmental information. However, linking environmental factors to final mineralogy requires gaining mechanistic-level information about their formation pathways. Here, we propose a mackinawite to greigite "corrosion" pathway, with H+ acting as an oxidant. 2026-03-23T16:48:42+01:00 https://doi.org/10.5194/ejm-38-123-2026 <b>High-spatial-resolution oxygen isotopic analysis to distinguish natural from synthetic corundum</b><br> Elena S. Sorokina, Axel K. Schmitt, Tobias Häger, and Jens Hopp<br> Eur. J. Mineral., 38, 123–134, https://doi.org/10.5194/ejm-38-123-2026, 2026<br> Natural ruby and sapphire are of the rarest gemstones. To further enable their identification from synthetic analogues, this study explores secondary ionization mass spectrometry (SIMS) oxygen isotope analysis. SIMS δ18O analysis of hydrothermal corundum yielded values between -7.84 ± 0.13 ‰ and -14.54 ± 0.13 ‰ (Vienna Standard Mean Ocean Water), which are atypical for natural corundum. SIMS δ18O analysis of corundum thus has strong potential to distinguish synthetic and natural corundum. 2026-03-18T16:48:42+01:00 https://doi.org/10.5194/ejm-38-117-2026 <b>IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) – Newsletter 89</b><br> Ferdinando Bosi, Frédéric Hatert, Marco Pasero, and Stuart J. Mills<br> Eur. J. Mineral., 38, 117–122, https://doi.org/10.5194/ejm-38-117-2026, 2026<br> 2026-03-11T16:48:42+01:00 https://doi.org/10.5194/ejm-38-103-2026 <b>Hydrogen diffusion in hydrous minerals from Raman and NanoSIMS mapping – implications for isotopic characterization of fluid–rock interactions</b><br> Bruno Reynard, Jannick Ingrin, Anne-Céline Ganzhorn, Julie Jonfal, Hélène Pilorgé, Clémentine Fellah, Nadège Hilairet, and Laurent Remusat<br> Eur. J. Mineral., 38, 103–116, https://doi.org/10.5194/ejm-38-103-2026, 2026<br> Interactions between minerals and water are fundamental to many geological processes on Earth, in meteorites, and on other planetary bodies, for instance, in the development of plate tectonics. In this study, we experimentally determine how quickly hydrogen isotopes are exchanged between minerals and fluids. We then explore how exchange rates can inform us about past interactions between rocks and water on the Earth and in meteorites using hydrogen isotope measurements in natural minerals. 2026-03-05T16:48:42+01:00 https://doi.org/10.5194/ejm-38-53-2026 <b>Deciphering crystal growth in a sector-zoned interpenetration twin of loparite from Mt Khibiny (Kola Peninsula, Russia) through atomic-scale characterisation of growth sectors and twin boundaries</b><br> Nina Daneu, José Alberto Padrón-Navarta, Martin Šala, Kristina Mervič, Gerlinde Habler, Goran Dražič, Petruša Borštnar, Aleksander Rečnik, and Rainer Abart<br> Eur. J. Mineral., 38, 53–73, https://doi.org/10.5194/ejm-38-53-2026, 2026<br> Loparite is a chemically complex perovskite oxide; the crystals often show zoning and develop as spinel-type interpenetration twins. Atomic-scale analyses of a sector-zoned twin from Mt Khibiny have revealed that cubic and octahedral sectors exhibit distinct elemental ordering, driven by differences in composition and slow cooling. The configuration of twin boundary contacts indicates twinning by nucleation, followed by independent growth of the domains in twin orientation from the melt.  2026-02-24T16:48:42+01:00 https://doi.org/10.5194/ejm-38-75-2026 <b>Crystal structure, chemical composition, and twinning of götzenite and wöhlerite from the Fohberg phonolite, Kaiserstuhl</b><br> Reinhard X. Fischer, Johannes Birkenstock, Georg Biskup, Lennart A. Fischer, Andreas Klügel, Shaghayegh Nezamabadi, and Simon Spürgin<br> Eur. J. Mineral., 38, 75–101, https://doi.org/10.5194/ejm-38-75-2026, 2026<br> Götzenite and wöhlerite were found as part of a fissure assemblage in the Fohberg phonolite (Kaiserstuhl, SW Germany) in close contact to each other. Götzenite shows rotation twinning on [001], and wöhlerite shows reflection twinning on (100). Götzenite represents a special case, where the twin domains are arranged in a certain way with the main axis nx of the optical indicatrix being parallel to the twin axis c in both domains. 2026-02-24T16:48:42+01:00 https://doi.org/10.5194/ejm-38-39-2026 <b>Zhenruite, (MoO3)2 ⋅ H2O, and tianhuixinite, (MoO3)3 ⋅ H2O, two new minerals in the MoO3–MoO3 ⋅ 2H2O system</b><br> Xiangping Gu, Hexiong Yang, Ronald B. Gibbs, and Guanghua Liu<br> Eur. J. Mineral., 38, 39–52, https://doi.org/10.5194/ejm-38-39-2026, 2026<br> Two new minerals, zhenruite, ideally (MoO3)2·H2O, and tianhuixinite, ideally (MoO3)3·H2O, are described. Zhenruite is monoclinic with space group P21/m and unit-cell parameters a = 9.6790(6), b = 3.70653(19), c = 7.1029(4) Å, β = 102.391(5)°, V = 248.89(2) Å3, and Z =2. Tianhuixinite is hexagonal with space group P63/m and unit-cell parameters a = 10.5963(12), c = 3.7216(4) Å, V = 361.88(9) Å3, and Z =2.  2026-01-15T16:48:42+01:00