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.

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.

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.

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 n_x of the optical indicatrix being parallel to the twin axis c in both domains.

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. 

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) ų, 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) ų, and Z =2. 

Spaltiite, ideally Tl₂Cu₂As₂S₅ (Z = 4), is a new thallium sulfosalt mineral discovered at the renowned Lengenbach locality in the Binn Valley, Canton of Valais, Switzerland. Spaltiite is a distinctly layered structure, with alternation of polar As–Cu layers and two somewhat different types of thallium layers.

This study examines how trace elements are distributed between melt and crystals during dacite crystallization (675–775 °C, 200 MPa) using a two-step experiment combining long-duration runs and a mineral trap technique. Residual melts were effectively separated and analysed. LA-ICP-MS (laser ablation inductively coupled plasma mass spectroscopy) data for elements like P, Y, Zr, Nb, Cs, Ce, Yb, and U reveal that, while Cs and U stay incompatible, other elements are affected by the type of crystallizing minerals.

Keutschite, Cu₂AgAsS₄, is a new mineral from the Uchucchacua polymetallic deposit, Oyon District, Catajambo, Lima Department, Peru. The ideal formula, derived from the crystal structure, is Cu₂AgAsS_4. The name honours Frank Keutsch (Harvard University), a German chemist who first drew attention to the mineral during his study of the minerals of the alabandite zone of the Uchucchacua deposit.

We conducted this research to gain an understanding of the unknown crystal structure of mineral launayite, which contains elements like antimony, copper, and lead. Using advanced X-ray techniques, we solved its crystal structure and discovered new details, such as unit cell parameters, symmetry, and substitutions. These findings provide accurate information about its relationship with rouxelite.

This study compares trace elements with the Spruce Pine pegmatite deposits in the United States and the pegmatite deposits in East Qinling in China to explore which types of deposits have the potential to become high-purity quartz raw material deposits. In addition, we also carried out technical purification and economic evaluation of the collected samples, aiming to provide guidance on technical purification and trace element determination of high-purity quartz deposits.

Åsgruvanite-(Ce) is a new rare Earth element (REE) mineral from Åsgruvan in Västmanland, Sweden, linked to Bastnäs-type mineralisation. The chemical formula ideally includes cerium, aluminium, silicon, arsenic, carbonate groups, chlorine, and fluorine. The mineral forms small, grey-green, lustrous grains with distinct cleavage and high density and is associated with carbonates and REE minerals like gadolinite and an allanite-like mineral. It has a unique layered crystal structure.