White and pale yellow crystal aggregates and microcrystals of the very rare mineral svyatoslavite from a the type and only known locality worldwide in Russia: Coal Mine #45, Kopeisk, Chelyabinsk Oblast, Russian Federation. Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY-SA 4.0
Svyatoslavite
Svyatoslavite is an IMA-recognized mineral species in the silicate class, with the chemical formula Ca(Al₂Si₂O₈).
It crystallizes in the monoclinic crystal system (space group P2_12_12).
Key properties: Mohs hardness 6; specific gravity 2.695; White streak; Vitreous luster; optically biaxial.
IMA symbol Svy, IMA status: approved, named in 1988.
Found in burning dumps, as a sublimate on fracture walls in coal, formed at about 700 ° C–900 ° C.
It is found associated with Anorthite, troilite, cohenite, fayalite, titanite, graphite.
The name refers to Svyatoslav Nestorovich Ivanov (1911–), Soviet geologist, Ural Scientific Center, Yekaterinburg (Sverdlovsk), Russia.