Iranite

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]

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]

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

[edit]
  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 Handbook of Mineralogy
  3. ^ a b c Mindat page for Iranite
  4. ^ Webmineral data for Iranite