Malachite (Dichromatic)

A wonderful example of dichroism (two colors) within the same composition. What appears to be a shaft of fibrous lighter green malachite contrasts the darker green hosting malachite. I imagine a slight change in copper concentration while forming may be the culprit. Subtle and beautiful. Ex Sam Koster Collection (who purchased it from Gilbert Gauthier at Tucson 1995).

Locality: Mindigi, Katanga Zaire (DRC)

Composition: Copper Carbonate Hydroxide