What is Zavaritskite?
Zavaritskite is a rare bismuth oxyhalide from bismuth-rich oxidation zones, usually found as pale crusts or tiny crystals with an unusually high density.
Mineralogy and structure
Reference formula: BiOF. Zavaritskite is tetragonal with the ideal formula BiOF. Its heavy bismuth chemistry gives high specific gravity, while fine crystal size makes locality and analytical documentation especially important; COD 9009163 is an exact structural reference. Zavaritskite is classified with halides and has tetragonal crystal symmetry. Typical hardness is 2–3 on the Mohs scale and specific gravity is approximately 7.5–7.8.
Colour, lustre and habit
Typical colours include white, yellow, grey, pale green. The usual tabular, granular, crusty habit and pearly, vitreous, adamantine lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Zavaritskite forms in or is associated with oxidation of bismuth-bearing hydrothermal veins and greisen or pegmatite environments. Important documented localities include Czechia, Germany, Bolivia, Russia and other bismuth districts.
A pale mineral with heavyweight chemistry
Zavaritskite rewards close viewing. A small pale crust can be a compelling specialist specimen when its bismuth-rich origin and exact locality are documented.
Collecting and care
Heavy bismuth-bearing material is brittle and delicate: protect crusts, avoid acids and dust, and keep a secure label with locality and analysis.
