Cahnite
Cahnite (Cahnit in German, Cahnita in Spanish, Канит in Russian[2]) is a brittle white or colorless mineral that has perfect cleavage and is usually transparent. It usually forms tetragonal-shaped crystals and it has a hardness of 3 mohs.[3][4] Cahnite was discovered in the year 1921.[2] It was named Cahnite to honor Lazard Cahn (1865–1940), who was a mineral collector and dealer.[3] It is usually found in the Franklin Mine, in Franklin, New Jersey.[4][3] Until the year 2002, when a sample of cahnite was found in Japan, that was the only known place that cahnite was located.[5] The geological environment that it occurs in is in pegmatites cutting a changed zinc orebody.[2][3][4] The chemical formula for cahnite is Ca2B[AsO4](OH)4.[4][6][7] It is made up of 26.91% calcium, 3.63% boron, 25.15% arsenic, 1.35% hydrogen, and 42.96% oxygen. It has a molecular weight of 297.91 grams.[4] Cahnite is not radioactive.[3] Cahnite is associated with these other minerals: willemite, rhodonite, pyrochroite, hedyphane, datolite, and baryte.[2]
Cahnite | |
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Cahnite on rhodonite | |
General | |
Category | Borate minerals |
Formula (repeating unit) | Ca2B[AsO4](OH)4 |
Strunz classification | 6.AC.70 |
Crystal system | Tetragonal |
Crystal class | Disphenoidal (4) (same H-M symbol) |
Space group | I4 |
Identification | |
Color | Colorless to white |
Cleavage | Perfect On {110} |
Tenacity | Brittle |
Mohs scale hardness | 3 |
Luster | Vitreous |
Diaphaneity | Transparent |
Density | 3.156 g/cm3 |
References | [1] |
References
- Mineralienatlas
- Mindat data sheet for Cahnite.
- Mineral Data sheet for Cahnite.
- Database entry from Mineral Collecting.
- Article stating that veins of cahnite were found in Okayama Prefecture. Archived 2012-02-17 at the Wayback Machine
- Database entry for Cahnite from Mincryst.
- Database entry for Cahnite from Japanese database.