Ottrelite

(Mn,Fe,Mg)₂Al₄Si₂O₁₀(OH)₄Strunz classification09.AF.85IdentificationFormula mass490.11ColorPistachio greenCrystal habitGranularTwinningPolysynthetic, {001}Cleavage{001} perfect; {110} likelyMohs scale hardness6–7LusterVitreous to nearly adamantine on cleavagesStreakGreenish, grayishDiaphaneityTranslucentSpecific gravity3.50Density3.52Dispersionr > v, strongReferences^[1][2][3]

Ottrelite is a form of chloritoid. Its empirical formula is (Mn,Fe,Mg)₂Al₄Si₂O₁₀(OH)₄.

See also

• List of minerals

References

External links

Media related to Ottrélite at Wikimedia Commons