This malachite is from the Katanga in the Katanga Copper Crescent in Katanga, Democratic Republic of the Congo. There are over 100 different mines and diggings in this area with 10 large operations. Local people mine in the closed locations for a long list of mineral specimens including secondary minerals such as malachite. It is a copper carbonate (Cu, C, H) that is found in the oxidation zones of copper ore bodies.This specimen consists of a quartzite matrix that hosts minor tenorite and gem-like formationa of primary malachite crystals. The malachite covers the quartzite with crystals and crystal stalactite / stalagmite formations. This piece measures 2 13/16 x 2 5/8 x 2 inches or 71 x 67 x 50 mm.