Malachite, Green Copper and Green Poison

Malachite is a copper carbonate hydroxide, a secondary mineral that forms where copper ore weathers, and its vivid banded green comes directly from the copper. It has one of the longest documented histories of any ornamental stone: ground to powder it was a green eye-paint and pigment in ancient Egypt, mined at Timna and in Sinai, and it remained an important artists green in Europe until synthetic pigments replaced it.

As a decorative stone the great Russian deposits of the Urals supplied the malachite veneer of Tsarist palaces. A genuine cautionary note belongs in any honest account: because it is a copper mineral, malachite dust is toxic, and lapidaries cut it wet and avoid breathing the powder. That real hazard sits oddly beside the modern crystal-healing habit of recommending it for wellbeing; the traditional uses were pigment and ornament, and no therapeutic use is supported.