Idocrase (Vesuvianite)
ID: 105
Idocrase (Vesuvianite)
Chemical Formula
Ca₁₀(Mg,Fe)₂Al₄(SiO₄)₅(Si₂O₇)₂(OH,F)₄
Hardness (Mohs)
6.5
Crystal System
Tetragonal
Streak
White
Luster
Vitreous
Diaphaneity
Transparent to Translucent
Color
Green, brown, yellow, blue, purple
Crystal Habit / Mode of Occurrence
Prismatic, massive
Density
3.3–3.5
Fun Facts
Idocrase is commonly found in skarns and is named after Mount Vesuvius, where it was first discovered. It belongs to the Vesuvianite Group and is brittle.