Chambersite Locality: Barbers Hill Salt Dome (Barbers Hill), Mont Belvieu , Chambers County, Texas , USA ( Locality at mindat.org ) Size: 0.5 x 0.5 x 0.5 cm. A rare, well-crystallized Texas mineral. Chambersite is a very rare borate found in a few salt domes, worldwide. This sharp, gemmy, purple crystal has classic pyramidal form, with good lustre, and comes from the Type Locality. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Chambersite
A manganese chloroborate belonging to the same borate series as boracite and ericaite.
Intro adapted from Wikipedia (CC BY-SA).
Chambersite is an IMA-recognized mineral species in the halide class, with the chemical formula Mn₃B₇O₁₃Cl.
It crystallizes in the orthorhombic crystal system (space group Pca2_1). It is a member of the Boracite structural group.
Key properties: Mohs hardness 7; specific gravity 3.49; [Vitreous.] luster; refractive index 1.738; optically biaxial.
IMA symbol Cbs, IMA status: approved, named in 1962.
Found in brine residues from extraction wells in salt domes.
It is found associated with Halite, anhydrite, gypsum.
The name refers to the location of the first known occurrence, Chambers Co., Texas, USA.