Malachite and keep evil spirits at bay. Malachite often results from the weathering of copper ores, and is often found together with azurite (Cu(CO)(OH)), goethite, and calcite. Except for its vibrant green color, the properties of malachite are similar to those of azurite and aggregates of the two minerals occur frequently. Malachite is more common than azurite and is typically associated with copper deposits around limestones, the source of the carbonate. Large quantities of malachite have been mined in the Urals, Russia. Ural malachite is not being mined at present, but G.N Vertushkova reports the possible discovery of new deposits of
Mineral a common formula of XY(Si,Al)O, where X and Y are both cations, with X typically bigger than Y; the pyroxenes are single-chain silicates that crystallize in either the orthorhombic or monoclinic crystal systems. Finally, a mineral variety is a specific type of mineral species that differs by some physical characteristic, such as colour or crystal habit. An example is amethyst, which is a purple variety of quartz. Two common classifications, Dana and Strunz, are used for minerals; both rely on composition, specifically with regards to important chemical groups, and structure. James Dwight Dana, a leading geologist of his time, first