Kassite | |
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General | |
Category | Hydroxide mineral |
Chemical formula | CaTi2O4(OH)2 |
Strunz classification | 04.DH.10 |
Identification | |
Molar mass | 235.09 |
Color | Brown red, colorless, light yellow |
Crystal habit | Pseudo hexagonal |
Crystal system | Monoclinic - Prismatic (2/m), space group: P21/a |
Cleavage | {010} Perfect |
Fracture | Brittle |
Mohs scale hardness | 5 |
Luster | Adamantine |
Streak | White |
Specific gravity | 3.42 |
Optical properties | Biaxial (–), 2V=58°, Dispersion very strong, r > v |
Refractive index | nα = 1.95, nβ = 2.13, nγ = 2.21 |
Birefringence | δ = 0.26 |
Pleochroism | none |
Other characteristics | Not radioactive |
References | [1][2] |
Kassite is a rare mineral with formula CaTi2O4(OH)2. It crystallizes in the orthorhombic crystal system and forms radiating rosettes and pseudo-hexagonal tabular crystals which are commonly twinned. Crystals are brownish pink to pale yellow and are translucent with an adamantine luster. Cleavage is distinct and the crystals are very brittle.
It was first described in 1965 from the Afrikanda pyroxenite massif, Kola Peninsula, Russia and was named for Nikolai Grigorievich Kassin (1885–1949), Russian geologist. It occurs as miarolytic cavity fillings of alkalic pegmatites in the Kola occurrence and in nepheline syenite in the Magnet Cove igneous complex of Arkansas, USA. Its mineral association includes cafetite, perovskite, titanite, rutile and ilmenite. It is polymorphous with cafetite.