https://ejm.copernicus.org/articles/ Recent articles of the journal European Journal of Mineralogy en https://doi.org/10.5194/ejm-38-575-2026 Synthesis of nano-porous ellipsoid hematite and the crystal growth mechanism Meirong Zong, Nshuti Cedrick, Wei Liang, Pinghua Zhu, Dongdong Liang, Haonan Liu, and Jiaxin Zou Eur. J. Mineral., 38, 575–582, https://doi.org/10.5194/ejm-38-575-2026, 2026 This study examines the growth of nanoporous ellipsoidal hematite via hydrothermal synthesis. Initially, iron oxyhydroxides agglomerate at 30 min, followed by needle-shaped FeOOH formation at 45 min. As the reaction progresses, FeOOH dehydrates and transforms into ellipsoidal hematite. After 120 min, lattice rearrangement results in nanoporous ellipsoidal hematite (~ 27 nm). These findings provide insight into hematite crystal growth mechanisms. Wed, 07 Oct 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-567-2026 Report of a rare, well-preserved lawsonite eclogite (Elekdağ, Central Pontides, Türkiye) Katherine F. Fornash, Charles Petty, Erkan Toraman, Gültekin Topuz, and Donna L. Whitney Eur. J. Mineral., 38, 567–574, https://doi.org/10.5194/ejm-38-567-2026, 2026 Lawsonite eclogites, which are a type of metamorphic rock, are important but rare archives of the conditions and processes in modern subduction zones. This report describes a 10th lawsonite eclogite locality (Elekdağ, Central Pontides, Türkiye). Mineral and bulk-rock compositions indicate P–T conditions of ~500°C, ~2.3 GPa, which are higher than the previously determined pressure conditions for the area but are similar to conditions recorded by other lawsonite eclogites. Fri, 02 Oct 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-557-2026 Quantitative analysis of aragonite-group carbonates synthetic mixtures using attenuated total reflection Fourier transform infrared Mahmoud Alkhatib, Nabil Thabteh, Fuad Al-Rimawi, and Mutaz Qutob Eur. J. Mineral., 38, 557–565, https://doi.org/10.5194/ejm-38-557-2026, 2026 Attenuated total reflection infrared spectroscopy was applied for qualitative and quantitative analysis of aragonite-group carbonates. This simple, fast, and accurate technique requires no sample preparation and can serve as a rapid alternative to X-ray diffraction. The novel aspect of this work is the development of calibration curves for quantifying strontianite and witherite in aragonite mixtures using absorbance ratios between  peaks, reducing variability from measurement conditions. Mon, 21 Sep 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-545-2026 The impact of exsolution textures in Fe–Ti oxide minerals on crushing strategies and vanadium and titanium pre-concentration Thomas Daniel van Gerve, Philippe Muchez, Ted Nuorivaara, and Olivier Namur Eur. J. Mineral., 38, 545–556, https://doi.org/10.5194/ejm-38-545-2026, 2026 Vanadium ores from the Bushveld Complex contain distinct microscopic mineral textures that strongly influence how efficiently vanadium can be extracted. Our study shows that some textures tightly intergrow minerals and hinder separation, while others form coarser structures that improve processing by magnetic and flotation methods. Identifying these textures is essential for optimizing vanadium ore processing and resource use. Fri, 21 Aug 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-531-2026 Belmonteite, CaMn2(AsO4)2(H2O)5 ⋅ 2H2O, a new arsenate mineral from the Mn ore deposits of the Graveglia Valley, eastern Liguria, Italy Cristian Biagioni, Jiří Sejkora, and Zdeněk Dolníček Eur. J. Mineral., 38, 531–543, https://doi.org/10.5194/ejm-38-531-2026, 2026 Belmonteite, CaMn2(AsO4)2(H2O)5·2H2O, is a new mineral discovered in the Mn ore deposits of eastern Liguria (Italy). Its crystal structure shows {010} layers of six-fold-coordinated Mn atoms decorated on both sides by (AsO4) groups and Ca atoms and connected through H bonds. The genesis of this mineral is related to the circulation of As-rich oxidizing fluids within the Mn ore deposits. The name honors Donato Belmonte for his contribution to the knowledge of the mineralogy of Liguria. Wed, 19 Aug 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-519-2026 Fengruiite, [Ag6Sb2S7][Ag9CuS2Te2], a new Ag–Sb–Te sulfosalt mineral from the Haopinggou Ag–Pb–Zn–Au deposit, eastern Qinling, China Yongfei Tian, Guowu Li, Ningyue Sun, Min Liu, Jingwen Mao, Yunpeng Dong, Peng Liu, Wei Jian, Wei Yao, Xiuquan Wang, and Huishou Ye Eur. J. Mineral., 38, 519–530, https://doi.org/10.5194/ejm-38-519-2026, 2026 We studied a newly discovered silver-rich mineral from an ore deposit in central China to understand how silver is stored in nature. Using microscopy, chemical, and crystal-structure tests, we found that this mineral is a new species with a unique tellurium-rich structure. Our results show that tellurium helped trap and concentrate silver in hot mineral-forming fluids, offering new clues to how silver-rich deposits form. Thu, 13 Aug 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-497-2026 A novel experimental approach to investigate element transport and isotope fractionation of Li and B in pegmatitic systems during fluid–melt interaction Christian Ronny Singer, Harald Behrens, Ingo Horn, Martin Oeser, Stefan Weyer, and François Holtz Eur. J. Mineral., 38, 497–518, https://doi.org/10.5194/ejm-38-497-2026, 2026 We developed a novel experimental setup to investigate the transport of Li and B between two melt reservoirs that were connected only via a fluid phase. This was used to simulate fluid exsolution occurring during late-stage pegmatite formation. We found that both Li and B were transported via the fluid, but the observed transport rates were low. It was shown experimentally that the Li isotopes fractionate between melt and fluid with the fluid being preferentially enriched in the heavier 7Li. Thu, 06 Aug 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-491-2026 IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) – Newsletter 92 Ferdinando Bosi, Frédéric Hatert, Marco Pasero, and Stuart J. Mills Eur. J. Mineral., 38, 491–495, https://doi.org/10.5194/ejm-38-491-2026, 2026 Fri, 31 Jul 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-477-2026 Preservation of water concentration in mantle xenoliths: a case study from Allègre and Ray Pic volcanoes (French Massif Central) Konstantinos Thomaidis, Jannick Ingrin, Etienne Deloule, Lydéric France, and Huan Chen Eur. J. Mineral., 38, 477–489, https://doi.org/10.5194/ejm-38-477-2026, 2026 Water in the form of hydrous-point-defect pyroxenes from mantle xenoliths is used to trace the water content in the lithospheric mantle. However, little is known about the mechanism that allows xenoliths to preserve deep hydrogen signatures. In particular, it is unknown how much of the water content of xenoliths is modified during the emplacement of lava and cooling at the surface and by the eruption mode (effusive versus explosive). In this work, we attempted to address these matters. Mon, 27 Jul 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-461-2026 Thermally activated multistep alteration of Fe2+-bearing fluorophlogopite revealed by in situ Raman spectroscopy Christian Reinberg, Stylianos Aspiotis, Thomas Malcherek, Stefan T. M. Peters, and Boriana Mihailova Eur. J. Mineral., 38, 461–475, https://doi.org/10.5194/ejm-38-461-2026, 2026 By applying in situ high-temperature Raman spectroscopy to (OH)-- and Fe2+-bearing fluorophlogopite we show that a phonon-driven structural instability near 600 K triggers the mobilization of interlayer K+ cations, which can act as charge carriers. Above 1100 K all H+ cations delocalize and can also contribute to transport processes. Above 1300 K oxidation of Fe takes place, along with limited dehydrogenation and dehydroxylation, facilitating partial K+ leakage and structural decomposition. Wed, 22 Jul 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-449-2026 Xianhuaite-(Ce), K2CeNb5O15, a new niobium mineral from the Bayan Obo deposit, China Bo Yang, Yuan Xue, Li Yang, Ningyue Sun, Guowu Li, Junfang Yu, Guoying Yan, Jianyong Liu, Yonggang Zhao, Wenxiang Meng, Zhenyu Chen, Lei Chen, Ze Liu, Zhao Yan, Xinyu Hou, Xin Ao, and Jinlong Wang Eur. J. Mineral., 38, 449–459, https://doi.org/10.5194/ejm-38-449-2026, 2026 Researchers studying the Bayan Obo deposit in northern China discovered an unknown mineral named xianhuaite-(Ce). The mineral contains the elements potassium, cerium, and niobium. Using microscopes, chemical analyses, and X-ray measurements, the researchers determined its structure and properties. The study shows that this mineral records the formation of rare earth and niobium ores in geological processes, improving our understanding of how these important resources formed. Tue, 21 Jul 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-431-2026 Fluorine-induced melting in the Ihalainen calcite-wollastonite marble deposit, Lappeenranta, Finland Robert F. Martin, Dirk Schumann, Markku J. Lehtinen, and Sebastian Fuchs Eur. J. Mineral., 38, 431–448, https://doi.org/10.5194/ejm-38-431-2026, 2026 The Ihalainen deposit in Finland produces wollastonite, a silicate of calcium. It formed 1.86 x 109 years ago; 240 x 106 years later, the area was invaded by a fluorine-rich granitic magma, which interacted with the marble host. The silicate magma lost silica and alkalis; the marble melted. A fluorine-rich vapor phase mobilized niobium, tantalum, and tin to form unknown minerals. The fluid was initially CO2-dominant and then became aqueous and formed a complex assemblage of alteration minerals. Mon, 20 Jul 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-419-2026 Mckelveyite group minerals – Part 5: Bainbridgeite-(NdCe), Na2Ba2NdCe(CO3)6●3H2O, a new neodymium and cerium-dominant species from Mont Saint-Hilaire, Canada Inna Lykova, Ralph Rowe, Glenn Poirier, Henrik Friis, Kelsie Ojaste, and Stephanie Barnes Eur. J. Mineral., 38, 419–429, https://doi.org/10.5194/ejm-38-419-2026, 2026 The paper describes bainbridgeite-(NdCe), Na2Ba2NdCe(CO3)6∙3H2O, from the famous Mont Saint-Hilaire complex, Quebec, Canada, the first known mineral with Ce and Nd atoms preferentially concentrated at two different sites of the structure Thu, 16 Jul 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-397-2026 Hydrothermal quartz genesis revealed by the combination of SEM charge contrast maps, FTIR mapping, and LA-ICP-MS trace element geochemistry Marko Bermanec, Nils B. Gies, Thomas Pettke, and Jörg Hermann Eur. J. Mineral., 38, 397–417, https://doi.org/10.5194/ejm-38-397-2026, 2026 We investigate how trace elements are incorporated into quartz formed in magmatic–hydrothermal ore deposits, key environments for critical metal enrichment. By tracking Li, B, Al, Ti, and OH defects across crystal growth zones we reveal distinct trace element zonation patterns linked to temperature and pressure evolution during crystallization. We demonstrate that combined trace element data and mapping of quartz can be a powerful tool for understanding ore deposit genesis and prospecting ores. Mon, 13 Jul 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-383-2026 Boron coordination in haplogranite glasses Jakob Rauscher, Michael Fechtelkord, Sandro Jahn, Julie A.-S. Michaud, Draupadi Mothan, Melanie J. Sieber, Robert B. Trumbull, Franziska D. H. Wilke, Max Wilke, and Bernd Wunder Eur. J. Mineral., 38, 383–396, https://doi.org/10.5194/ejm-38-383-2026, 2026 Boron and its isotopes, 11B and 10B, can track magmatic–hydrothermal processes, but this requires knowing how the isotopes fractionate between melt and fluid, which depends on B coordination. This is known for aqueous fluids but not for silicate melts. We determined B coordination by nuclear magnetic resonance in granitic glass with variable water content and alkali–alumina ratios. The results provide a way to estimate B coordination and melt–fluid fractionation for variable melt compositions. Thu, 09 Jul 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-373-2026 Yttrotungstite-(Nd), a new mineral species from the Nyakabingo tungsten mine, Kigali, Rwanda Frédéric Hatert, Simon Philippo, Pietro Vignola, and Maël Guennou Eur. J. Mineral., 38, 373–382, https://doi.org/10.5194/ejm-38-373-2026, 2026 Yttrotungstite-(Nd) is a new mineral species discovered in the Nyakabingo tungsten mine, Kigali, Rwanda. The mineral occurs in the oxidized zones of the deposit, where it forms tiny yellow-orange tabular crystals that reach a length of maximum of 100 µm, and frequently form radiated groups. The dominant form is {010}, and a twinning has been observed parallel to (001). Electron microprobe analyses and structural data, confirming that the species belongs to the yttrotungstite group. Tue, 07 Jul 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-353-2026 Dehydration reactions in guano-derived minerals: the taranakite-to-francoanellite transformation Yuri Galliano, Nicola Campomenosi, Fabio Bellatreccia, Donato Belmonte, Jo De Waele, and Cristina Carbone Eur. J. Mineral., 38, 353–372, https://doi.org/10.5194/ejm-38-353-2026, 2026 Deposits of bat guano in cave environments host diverse assemblages of secondary minerals, which can go through partial dehydration processes in response to varying environmental conditions. In this article, we investigate the thermodynamics and kinetics which lead guano-derived taranakite to lose part of its structural water and transform into francoanellite. Our results allow us to present evidence-based hypotheses to explain the occurrence of the latter in natural environments. Mon, 22 Jun 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-347-2026 IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) – Newsletter 91 Ferdinando Bosi, Frédéric Hatert, Marco Pasero, and Stuart J. Mills Eur. J. Mineral., 38, 347–352, https://doi.org/10.5194/ejm-38-347-2026, 2026 Fri, 19 Jun 2026 22:07:03 +0200 https://doi.org/10.5194/ejm-38-337-2026 Piilonenite-(Nd), NaNd(CO3)2 ⋅ 3H2O, a new neodymium-dominant carbonate mineral from Mont Saint-Hilaire, Quebec, Canada Inna Lykova, Ralph Rowe, Simon J. Teat, Glenn Poirier, and Stephanie Barnes Eur. J. Mineral., 38, 337–345, https://doi.org/10.5194/ejm-38-337-2026, 2026 The paper is on the new mineral species piilonenite-(Nd), a new Nd-dominate carbonate with no closely related minerals or synthetic compounds from Mont Saint-Hillarie, Canada. Fri, 19 Jun 2026 22:07:04 +0200 https://doi.org/10.5194/ejm-38-325-2026 Argentotennantite-(Fe), Ag6(Cu4Fe2)As4S13, a new member of the tetrahedrite group from the San Genaro mine, Peru: occurrence and crystal structure Jiří Sejkora, Dalibor Velebil, Cristian Biagioni, Zdeněk Dolníček, and Jaroslav Hyršl Eur. J. Mineral., 38, 325–336, https://doi.org/10.5194/ejm-38-325-2026, 2026 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. Thu, 11 Jun 2026 22:07:04 +0200