Usaldasite

Usaldasite is a proposed mineral name for a rare aluminosilicate carbonate phase described from crystals found in the Usalda Basin. The precise chemical formula has not been published, and analyses indicate a mixed aluminum-silicate framework with carbonate groups and trace elements. Due to the scarcity of material, crystallography and definitive chemistry are still under review.

It was first reported by a field team surveying the Usalda Basin and was named after the locality, following common mineral-naming practice. As such, its status as a mineral species remains provisional pending further study.

Physical properties reported for available grains describe a vitreous to pearly luster, colorless to pale yellow crystals, and a Mohs hardness estimated around 5–6. Specimens are typically microcrystalline or tabular; no robust cleavage pattern has been established. Specific gravity is estimated near 3.0. Pleochroism has not been observed in the limited material.

Occurrence is currently limited to a single occurrence in the Usalda Basin's metamorphosed carbonate rocks, with associations including calcite, dolomite, and phlogopite. Because of the tiny sample size, the mineral's recognition by major authorities has not been confirmed, and additional specimens are sought for validation.

Etymology and classification: the name honors the Usalda region and follows standard -ite mineral nomenclature. See also: minerals named after places; list of mineral species.