Iranite

Iranite (Persian: ایرانیت) is a triclinic lead copper chromate silicate mineral with formula Pb10Cu(CrO4)6(SiO4)2(F,OH)2. It was first described from an occurrence in Iran. It is the copper analogue of hemihedrite (Pb10Zn(CrO4)6(SiO4)2(F,OH)2).[3]

Iranite
General
CategorySilicate mineral
Formula
(repeating unit)
Pb10Cu(CrO4)6(SiO4)2(F,OH)2
IMA symbolIrn[1]
Strunz classification7.FC.15
Crystal systemTriclinic
Space groupTriclinic pedial
H-M symbol: (1)
Space group: P1
Unit cella = 10.02 Å, b = 9.54 Å, c = 9.89 Å; α = 104.5°, β = 66°, γ = 108.5°; Z=1
Identification
ColorBrown to orange
Crystal habitEquant to flattened euhedral crystals
Mohs scale hardness3
LusterVitreous
StreakYellow
Specific gravity5.8
Optical propertiesBiaxial
Refractive indexnα = 2.250 - 2.300 nγ = 2.400 - 2.500
Birefringenceδ = 0.150 - 0.200
References[2][3][4]

It occurs as an oxidation product of hydrothermal lead-bearing veins. Associated minerals include dioptase, fornacite, wulfenite, mimetite, cerussite and diaboleite.[2] It was first described in 1970 for an occurrence in the Sebarz Mine, northeast of Anarak, Iran.[3][2]

References


This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.