Description | The green material is malachite. Malachite, Cu2(CO3)(OH)2 (copper carbonate hydroxide) is well-known for its color. High-quality samples are prized as semi-precious stones. When gemmy, its banded light and dark green appearances are one-of-a-kind, and give it a unique ornamental quality unlike that of any other stone. In this sample, it is fine grained and massive. Malachite is often associated with other copper minerals; the black-brown material in this sample is cuprite, Cu2O. This specimen is 10 cm across. |