Malachite  Malachite is a copper carbonate hydroxide mineral, with the formula Cu2CO3 (OH)2. This opaque, green-banded mineral crystallizes in the monoclinic crystal system, and most often forms botryoidal, fibrous, or stalagmitic masses, in fractures and deep, underground spaces, where the water table and hydrothermal fluids provide the means for chemical precipitation. Individual crystals are rare, but occur as slender to acicular prisms. Pseudomorphs after more tabular or blocky azurite crystals also occur. The stone's name derives (via , , and Middle English "melochites") from Greek Μολοχίτης λίθος "molochites lithos", "mallow-green stone", from μολόχη "molochē", variant of μαλάχη "malāchē", "mallow". The mineral was given this name due to its resemblance to the leaves of the mallow plant. Malachite was extensively mined at the Great Orme Mines in Britain 3,800 years ago, using stone and bone tools. Archaeological evidence indicates that mining activity ended , with up to 1,760 tonnes of copper being produced from the mined Malachite. Archaeological evidence indicates that the mineral has been mined and smelted to obtain copper at Timna Valley in Israel for more than 3,000 years. Since then, malachite has been used as both an ornamental stone and as a gemstone. Malachite often results from the weathering of copper ores, and is often found with azurite (Cu3(CO3)2(OH)2), 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 malachite in the Urals. It is found worldwide including in the Democratic Republic of the Congo; Gabon; Zambia; Tsumeb, Namibia; Mexico; Broken Hill, New South Wales; Lyon, France; Timna Valley, Israel; and the Southwestern United States, most notably in Arizona.