image

A mineral is a naturally occuring, homogeneous, solid with a crystalline atomic structure. Crystallinity implies that a mineral has a definite and limited range of composition, and that the composition is expressible as a chemical formula. Some definitions of minerals give them as inorganic materials, however both diamonds and graphite are considered minerals, and both are primarily comprised of carbon, which would make them organic. So this leads me, as an engineer, to believe that mineralogists do not have a good, precise definition of a mineral, but rather a loose definition. The definition above, is the most inclusive and would include all substances currently described as minerals. The key items that make something a mineral are occurring naturally, and the definite crystal structure, that is expressible as a chemical formula. Rocks that do not meet this criteria are referred to as amorphis - not having a definite structure or expressible as a chemical formula. Some elements that occur naturally and are minerals are arsenic, bismuth, platinum, gold, silver, copper, and sulphur.

THE DEFINITION OF ORGANIC: Organic chemistry is the study of those substances containing carbon in combination with hydrogen (H), and a few other non metals, namely oxygen (O), nitrogen (N), sulfur (S) and the halogens (F2, Cl2, Br2, and I2).








Malachite is a copper bearing mineral, with as much as 58% copper content. The distinctive bright-green hydrous CARBONATE MINERAL malachite is a common but minor ore of copper. It is usually found in copper deposits associated with LIMESTONE, occurring with AZURITE as the weathering product of other copper ore minerals. Hardness is 3 1/2 to 4, streak is pale green, specific gravity is 3.9 to 4.1, and luster is adamantine to silky. Malachite forms needlelike prismatic crystals (monoclinic system) that are rarely distinct; it is usually found in granular, earthy, or fibrous masses and rounded, banded crusts. Malachite is used as a decorative stone when cut and polished, a semiprecious gem, and a green pigment.

Half of the world's copper deposits are in the form of chalcopyrite ore. All important copper-bearing ores fall into two main classes: oxidized ores and sulfide ores.

Sulfide ores are more important commercially. Ores are removed either by open-pit or by underground mining. Ores containing as little as 0.4% copper can be mined profitably in open-pit mining, but underground mining is profitable only if an ore contains 0.7%-6% copper. The oxidized ores, such as cuprite and tenorite, can be reduced directly to metallic copper by heating with carbon in a furnace, but the sulfide ores, such as chalcopyrite and chalcocite, require a more complex treatment in which low-grade ores have to be enriched before smelting begins. This involves the ore-flotation process, in which the ore is crushed and powdered before it is agitated with water containing a foaming agent and an agent to make the copper-bearing particles water-repellent. These particles accumulate in the froth on the surface of the flotation tank, and this froth is skimmed off and heated to about 800 deg C to remove some of the water as well as antimony, arsenic, and sulfur, which are also present.