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(mineralogy) A triclinic-pedial mineral containing chromium, copper, fluorine, hydrogen, lead, oxygen, and silicon.

Iranite – Category: Chromate minerals – Formula: Pb₁₀Cu(CrO₄)₆(SiO₄)₂(F,OH)₂ – IMA symbol: Irn – Strunz classification: 7.FC.15 – Crystal system: Triclinic – Space group: Triclinic pedial (H-M symbol: (1), Space group: P1) – Unit cell: a = 10.02 Å, b = 9.54 Å, c = 9.89 Å; α = 104.5°, β = 66°, γ = 108.5°; Z = 1 – Color: Brown to orange – Crystal habit: Equant to flattened euhedral crystals – Mohs scale hardness: 3 – Luster: Vitreous – Streak: Yellow – Specific gravity: 5.8 – Optical properties: Biaxial – Refractive index: nα = 2.250 – 2.300, nγ = 2.400 – 2.500 – Birefringence: δ = 0.150 – 0.200.