Bonshtedtite
Bonshtedtite is an IMA-recognized mineral species in the phosphate class, with the chemical formula Na₃Fe²⁺(PO₄)(CO₃).
It crystallizes in the monoclinic crystal system (space group P2_1/m). It is a member of the Bradleyite structural group.
Key properties: Mohs hardness 4; specific gravity 2.95–3.16; Vitreous, pearly on cleavages luster; optically biaxial.
IMA symbol Bsd, IMA status: approved, named in 1981.
Found in veinlets in association with alkali-carbonate metasomatism of alkalic massifs.
It is found associated with Shortite, thermonatrite, eitelite, neighborite, trona, burbankite, barentsite, siderite, aegirine.
The mineral was named to honor Elsa Maksimilianovna Bonshtedt-Kupletskaya (1897–1974), Russian specialist in mineralogy of alkalic massifs.