This chrysocolla and copper mineral mix is from Kolwezi in the Katanga province of the Congo. The piece has been cut and polished to a gem luster. The process reveals and accentuates the different generations of chrysocolla, malachite and other copper minerals deposited in concentric bands and layers within the formations. The cross-sectional cuts show the alternating and different colors of the mineral deposits. This piece measures approximately 6 3/4 x 6 1/4 x 2 3/4 inches or 174 x 158 x 70 mm.