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www.mineralgallery.co.za Minerals K-O |
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Malachite |
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Name
Malachite
Chemistry
Cu2(CO3)(OH)2, Copper Carbonate Hydroxide
Uses
As a minor ore of copper or as a stone used for carvings and ornaments
Color
Green shades with concentric bands of lighter and darker green
Hardness
3.5-4
Specific gravity.
3.54-4.1
Many beautiful specimens of Malachite contain special combinations with other minerals, such as the azure blue of azurite, the baby blue of Chrysocolla, or the rusty red of limonite.
It occurs as a massive botryoidal form that has concentric bands of lighter and darker green. It is a beautiful stone to have in your collection.
Malachite (Cu2CO3(OH)2) is a carbonate, which are among the most widely distributed minerals in the Earth's crust.
Carbonate minerals other than simple carbonates include hydrated carbonates, bicarbonates, and compound carbonates.
Malachite is a member of this third group, as are the minerals, Bastnasite, doverite, and azurite.
Malachite is a secondary mineral of copper, which means it is formed when copper minerals are altered by other chemicals. It occurs when carbonated water interacts with copper minerals, or when a solution of copper interacts with limestone. Malachite is opaque and always green. Because of its presence in nearly all oxidized copper deposits, malachite serves as a prospecting guide for copper.
Malachite crystals sometimes form as needles that fan out from the rock in which they are embedded. More often, malachite forms as a mass with concentric bands of light and dark green. Such specimens are almost always internally banded in different shades of green, and can be seen when a specimen is polished or cut open. When the bands consist of concentric rings specimens are highly prized.
Because of its beauty and relative softness, polished, banded Malachite has been carved into ornaments and worn as jewelry for thousands of years. In some cultures it was thought to be a protection from evil if worn as jewelry. Malachite has also been widely used as an ornamental stone. In Czarist Russia it was used to make the columns of St. Isaac's Cathedral in Leningrad. The original material, from which ornaments and jewelry were made since the earliest times came from an enormous deposit in the Ural Mountains of Russia, where massive globular specimens were found.
We have available the massive kinds from Zambia and the delicate specimens from Tsumeb.
Crystals are acicular or fibrous and form in tufts and encrustations. It occurs in Zaire; Namibia; Ural mountains, Russia; Australia; England and Arizona, USA.
