Axinite is a brown to violet-brown, or reddish-brown bladed group of minerals composed of calcium aluminium boro-

silicate In chemistry, a silicate is any member of a family of polyatomic anions consisting of silicon and oxygen, usually with the general formula , where . The family includes orthosilicate (), metasilicate (), and pyrosilicate (, ). The name is al ...

, . Axinite is pyroelectric and piezoelectric. The axinite group includes: *Axinite-(Fe) or ferroaxinite, Ca₂Fe²⁺Al₂BOSi₄O₁₅(OH) iron rich, clove-brown, brown, plum-blue, pearl-gray * Axinite-(Mg) or magnesioaxinite, Ca₂MgAl₂BOSi₄O₁₅(OH) magnesium rich, pale blue to pale violet; light brown to light pink *Axinite-(Mn) or manganaxinite, Ca₂Mn²⁺Al₂BOSi₄O₁₅(OH) manganese rich, honey-yellow, clove-brown, brown to blue *Tinzenite, (CaFe²⁺Mn²⁺)₃Al₂BOSi₄O₁₅(OH) iron – manganese intermediate, yellow, brownish yellow-green Axinite is sometimes used as a gemstone.Tables of Gemstone Identification By Roger Dedeyne, Ivo Quintens p.147

Gallery

File:Axinite-64246.jpg, Clove-brown axinite crystals to 2.3 cm set atop matrix from the West Bor Pit at

Dalnegorsk Dalnegorsk (russian: Дальнего́рск, lit. ''far in the mountains'') is a town in Primorsky Krai, Russia. Population: Name It was formerly known from its founding in 1897 as Tetyukhe (russian: Те́тюхе; ; literally meaning "riv ...

, Russia File:Axinite-60191.jpg, Chloritized bladed crystals of Axinite forming on Adularia from the

Swiss Alps The Alpine region of Switzerland, conventionally referred to as the Swiss Alps (german: Schweizer Alpen, french: Alpes suisses, it, Alpi svizzere, rm, Alps svizras), represents a major natural feature of the country and is, along with the Swiss ...

File:Tinzenite-Calcite-172430.jpg, Tinzenite on Calcite, 4.5 × 3.5 × 3 cm. Wessels Mine, Kalahari manganese fields, Northern Cape Province, South Africa File:Axinite-(Mn)-239862.jpg, Manganaxinite (Axinite-(Mn)), with sharp curving crystals to 4 cm. West Bor Pit at

, Russia

References

{{Manganese minerals Calcium minerals Iron(II) minerals Manganese(II) minerals Aluminium minerals Sorosilicates Triclinic minerals Luminescent minerals Gemstones Minerals in space group 2