Outstanding single pinkish-violet crystal of the extremely rare mineral magbasite from the TL: Bayan Obo Deposit, Baotou League, Inner Mongolia, China Peoples Republic. Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY-SA 4.0
Magbasite
Magbasite is an IMA-recognized mineral species in the silicate class, with the chemical formula KBaFe³⁺Mg₇Si₈O₂₂(OH)₂F₆.
It crystallizes in the orthorhombic crystal system (space group Cmma).
Key properties: Mohs hardness 5; specific gravity 3.41; Vitreous luster; optically biaxial.
IMA symbol Mgb, IMA status: approved, named in 1965.
Found in thin veins cutting ferrodolomite- and siderite-carbonatites (Canada).
It is found associated with Phlogopite, quartz, siderite, Fe-rich dolomite, Nb-rich rutile, bafertisite, monazite-(Ce), rare-earth fluoro-carbonates (bastnäsite-parisite).
The name refers to MAGnesium and BArium in its chemical composition.