Chlorocalcite

Chlorocalcite
General
Category Halide mineral
Formula
(repeating unit)
KCaCl3
Strunz classification 03.AA.40
Crystal symmetry Orthorhombic; Space group: Pnma (from synthetic crystals)
Unit cell a = 7.35 Å, b = 10.44 Å, c = 7.25 Å; Z=5
Identification
Formula mass 185.54 g/mol
Color White, tinged violet
Crystal habit Prismatic or tabular cube-like crystals
Crystal system Orthorhombic, pseudo cubic
Cleavage Perfect on {001}, good on {010} and {100}
Mohs scale hardness 2.5-3
Diaphaneity Transparent to semi-transparent
Density 2.16 calculated
Optical properties Biaxial (–)
Refractive index ~1.52
Birefringence weak
Solubility In water
Other characteristics Deliquescent
References [1][2][3]

Chlorocalcite is a rare potassium calcium chloride evaporite mineral with formula: KCaCl3. It is found in active volcanic fumaroles.

It was first described in 1872 for an occurrence on Mount Vesuvius and given the name for its calcium content previous to discovering that it also contained potassium.[1][2] It has also been reported from the Desdemona Mine, Peine, Lower Saxony, Germany.[1]

References

This article is issued from Wikipedia - version of the Wednesday, March 20, 2013. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.