vastustin

Vastustin is a rare metallic silicate mineral and the corresponding synthetic form studied for potential industrial use. In natural samples, vastustin occurs as small, well-formed prismatic crystals embedded in ultramafic rock matrices and is typically associated with olivine, pyroxene, and magnetite. The mineral is named in honor of two researchers who contributed to its discovery and study, giving the name vastustin.

Crystal structure and composition: Vastustin is described as a layered silicate with a mixed metal occupancy, primarily containing iron and magnesium cations in octahedral coordination with silicate tetrahedra. It crystallizes in the monoclinic system and shows a metallic to sub-metallic luster with a steel-gray color. Hardness on Mohs scale is reported around 6.5–7, and typical measured density is about 3.2–3.4 g/cm3. It exhibits weak pleochroism if any, and has small variations in optical properties depending on impurities.

Occurrence and formation: Natural formation is linked to high-temperature, high-pressure metamorphic or magmatic environments, possibly as a late-stage crystallization product in ultramafic magmas. It may form under reducing conditions that stabilize mixed valence iron cations.

Synthesis and applications: The synthetic version can be produced by solid-state reaction at elevated temperatures and pressures, yielding polycrystalline materials suitable for abrasive papers, refractory catalysts, or catalyst supports. Research is ongoing to assess stability, oxidation behavior, and potential electronic applications.

Status: Vastustin has not been approved as a formally recognized mineral species by the IMA and remains primarily of academic interest and material science research.