Aliettite

Aliettite
Aliettite
General
CategoryPhyllosilicates
IMA symbolAli[1]
Strunz classification9.EC.60
Crystal systemHexagonal
Unknown space group
Unit cella = 5.216, c = 24.6 [Å]; Z = 1
Identification
ColorColorless, pale yellow or green.
Crystal habitPlaty
Mohs scale hardness1–2
LusterEarthy (dull)
StreakWhite
DiaphaneityTranslucent
Refractive index1.558–1.567
References[2][3][4][5]

Aliettite is a complex phyllosilicate mineral of the smectite group with a formula of (Ca0.2Mg6(Si,Al)8O20(OH)4·4H2O)[2] or [Mg3Si4O10(OH)2](Ca0.5,Na)0.33(Al,Mg,Fe2+)2−3(Si,Al)4O10(OH)2·n(H2O).[3][4]

It is a soft, colorless to pale yellow or green earthy mineral which crystallizes in the monoclinic system as minute tabular to platy crystals.[2]

It was first described in 1968 for an occurrence in Monte Chiaro, Albareto, Parma Province, Emilia-Romagna, Italy and named for the Italian mineralogist Andrea Alietti (born 1923).[2]

It occurs in serpentinized ophiolites and their residual soil. It also occurs in altered dolomite. Associated minerals include talc, chlorite, serpentine and calcite.[4] In addition to the type locality in Italy it has been reported from Kinshasa, Katanga;[4] the Chelyabinsk Oblast of the southern Urals and the Turii alkaline Massif of the Kola Peninsula in Russia; the Zirabulak Mountains of Uzbekistan; and the Goldstrike Mine of Eureka County, Nevada, US.[2]

  1. ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
  2. ^ a b c d e Aliettite. Mindat.org
  3. ^ a b Aliettite. Webmineral
  4. ^ a b c d Aliettite. Handbook of Mineralogy
  5. ^ Mineralienatlas