Yellow microcrystals of the extremely rare Sn mineral from the type locality in Morocco (Wadi Beht, El Hammam, Meknès Prefecture, Fès-Meknès Region, Morocco) and only one of the two known localities worldwide. Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY-SA 4.0
Burtite
Burtite is an IMA-recognized mineral species in the oxides & hydroxide class, with the chemical formula CaSn⁴⁺(OH)₆.
It crystallizes in the cubic crystal system (space group Pn3). It is a member of the Perovskite structural group.
Key properties: Mohs hardness 3; specific gravity 3.28; Vitreous; surface typically earthy due to alteration luster; optically uniaxial.
IMA symbol Bu, IMA status: approved, named in 1980.
From a garnetite in a tin-bearing skarn, formed under conditions of relatively low temperature and low XCO2.
It is found associated with Wickmanite, stokesite, datolite, pectolite, andradite, wollastonite, malayaite, clinopyroxene, löllingite.
The name refers to Dr. Donald McLain Burt (1943–), Professor of Mineralogy, Arizona State University, Tempe, Arizona, USA, authority on mineral equilibria in skarn and greisen deposits.