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) Axinite-(Mg) is a borosilicate mineral of aluminum, calcium and magnesium of the axinite group, with magnesium as the dominant cation in the place of the structure that can also be occupied by iron and manganese. It was discovered in gem material ...

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 "river ...

, 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