Camaraite, Ba_3NaTi_4(Fe~(2+),Mn)_8(Si_2O_7)_4O_4(OH,F)_7. I. A new Ti-silicate mineral from the Verkhnee Espe Deposit, Akjailyautas Mountains, Kazakhstan

摘要

Camaraite, ideally Ba_3NaTi_4(Fe~(2+),Mn)_8(Si_2O_7)_4O_4(OH,F)_7, is a new mineral from the Verkhnee Espe deposit, Akjailyautas Mountains, Kazakhstan. It occurs as intergrowths with bafertisite and jinshajiangite in separate platy crystals up to 8 mm × 15 mm × 2 mm in size, or as star-shaped aggregates of crystals with different orientations. Individual crystals are orange-red to brownish-red, and are platy on {001}. Camaraite is translucent and has a pale-yellow streak, a vitreous lustre, and does not fluoresce under cathode or ultraviolet light. Cleavage is {001} perfect, no parting was observed, and Mohs hardness is <5; the mineral is brittle. The calculated density is 4.018 g cm~(-3).