brauserites

Brauserites is the name given to a proposed aluminosilicate mineral described in a 2021 study by Brauser and colleagues. It has not been formally approved as a mineral species by the International Mineralogical Association (IMA) and remains unrecognized in official catalogs.

Etymology and discovery: The name honors geologist Elena Brauser, who reported the initial occurrences in the Central Alps. The original description outlined a general formula and a structural model, noting variability in composition and the tentative nature of the identification pending further validation.

Composition and structure: The described composition centers on a silicate framework with aluminum and barium as major cations and iron as a variable substituent. The provisional formula is often listed as Ba(Al,Fe)2Si6O16(OH)2, with trace manganese and sodium in solid solution. The proposed crystal system is monoclinic, reflecting layered silicate characteristics in the initial model.

Occurrence and paragenesis: Reports place brauserites in hydrothermal veins within felsic plutonic rocks, where it occurs in association with quartz, albite, and muscovite. Formation is thought to require high-temperature, Ba-rich fluid conditions, with stability limited to specific pressure–temperature and chemical environments.

Physical properties and status: Described crystals are typically pale yellow to brown, with a vitreous luster. Hardness is estimated around 5.5 on the Mohs scale, and the specific gravity is near 3.2. Because the species has not received IMA recognition, some databases list brauserites as a nomen nudum or a tentative name; additional peer‑reviewed work is needed for validation and formal publication.

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