Sharp brown crystal of batisite, a very rare mineral known from a very few localities worldwide. Named from the chemical composition. From: Löhley, Üdersdorf, Daun, Eifel, Rhineland-Palatinate, Germany. — Photo: David Hospital · CC BY-SA 4.0
Batisite
Batisite is an IMA-recognized mineral species in the silicate class, with the chemical formula Na₂BaTi₂O₂(Si₂O₆)₂.
It crystallizes in the orthorhombic crystal system (space group Ima2). It is a member of the Batisite structural group.
Key properties: Mohs hardness 6; specific gravity 3.432; Rose-brown streak; Vitreous to slightly oily luster; optically biaxial.
IMA symbol Bat, IMA status: approved, named in 1960.
Found in aegirine-arfvedsonite-microcline pegmatites in dunites (Inagli massif, Russia).
It is found associated with Microcline, nepheline, aegirine, arfvedsonite, lorenzenite, uranian thorite, eudialyte, apatite, orthoclase (Inagli massif, Russia).
The name refers to Ba, Ti, Si in the composition.