From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Cahnite on rhodonite
CategoryBorate minerals
(repeating unit)
IMA symbolCah[1]
Strunz classification6.AC.70
Crystal systemTetragonal
Crystal classDisphenoidal (4)
(same H-M symbol)
Space groupI4
ColorColorless to white
On {110}
Mohs scale hardness3
Density3.156 g/cm3

Cahnite (Cahnit in German, Cahnita in Spanish, Канит in Russian[3]) 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.[4][5] Cahnite was discovered in the year 1921.[3] It was named Cahnite to honor Lazard Cahn (1865–1940), who was a mineral collector and dealer.[4] It is usually found in the Franklin Mine, in Franklin, New Jersey.[5][4] Until the year 2002, when a sample of cahnite was found in Japan, that was the only known place that cahnite was located.[6] The geological environment that it occurs in is in pegmatites cutting a changed zinc orebody.[3][4][5] The chemical formula for cahnite is Ca2B[AsO4](OH)4.[5][7][8] 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.[5] Cahnite is not radioactive.[4] Cahnite is associated with these other minerals: willemite, rhodonite, pyrochroite, hedyphane, datolite, and baryte.[3]


  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85: 291–320.
  2. ^ Mineralienatlas
  3. ^ a b c d Mindat data sheet for Cahnite.
  4. ^ a b c d e Mineral Data sheet for Cahnite.
  5. ^ a b c d e Database entry from Mineral Collecting.[permanent dead link]
  6. ^ Article stating that veins of cahnite were found in Okayama Prefecture. Archived 2012-02-17 at the Wayback Machine
  7. ^ Database entry for Cahnite from Mincryst.
  8. ^ Database entry for Cahnite from Japanese database.