Chlorocalcite

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

Chlorocalcite
General
CategoryHalide mineral
Formula
(repeating unit)
KCaCl3
IMA symbolCcal[1]
Strunz classification3.AA.40
Crystal systemOrthorhombic
Crystal classDipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)
Space groupPnma (from synthetic crystals)
Unit cella = 7.35 Å, b = 10.44 Å,
c = 7.25 Å; Z = 4
Identification
Formula mass185.54 g/mol
ColorWhite, tinged violet
Crystal habitPrismatic or tabular cube-like crystals, pseudo cubic
CleavagePerfect on {001}, good on {010} and {100}
Mohs scale hardness2.5-3
DiaphaneityTransparent to semi-transparent
Density2.16 calculated
Optical propertiesBiaxial (–)
Refractive index~1.52
Birefringenceweak
SolubilityIn water
Other characteristicsDeliquescent
References[2][3][4][5]

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.[3][4] It has also been reported from the Desdemona Mine, Peine, Lower Saxony, Germany.[3]

References

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.