Zoisite

Zoisite is a mineral from the sorosilicate group, composed of hydrated calcium and aluminum silicate (Ca₂Al₃(SiO₄)(Si₂O₇)O(OH)). It appears in shades of green, grey, pink, or brown, and can form prismatic crystals or massive aggregates.

It mainly forms in metamorphic rocks, particularly schists and gneisses.

Tanzanite is its blue to blue-violet gem variety, known for its remarkable colors and exclusively sourced from Tanzania.