Brief description of the main minerals.
Diamond - the hardest of all minerals. In composition, it is pure carbon. It occurs in placers and in the form of inclusions in igneous rocks. Diamonds are colorless, but there are also painted in various colors. A faceted diamond is called a diamond. Its weight is usually measured in carats (1 carat = 0.2 g). The largest diamond found in South Africa: it weighed more than 3,000 carats. Most diamonds are mined in Africa (98% of the mining in the capitalist world). In Russia, large diamond deposits are located in Yakutia. Transparent crystals are used to make gemstones. Until 1430, diamonds were considered ordinary gemstones. The trendsetter for them was the Frenchwoman Agnes Sorel. Opaque diamonds, due to their hardness, are used in industry for cutting and engraving, as well as for polishing glass and stone.
Gold - is a soft malleable yellow metal, heavy, does not oxidize in air. In nature, it occurs mainly in its pure form (nuggets). The largest nugget, weighing 69.7 kg, was found in Australia. Gold is also found in the form of placers - this is the result of weathering and erosion of the deposit, when grains of gold are released and carried into rivers, forming placers. Gold is used in the manufacture of precision instruments and various jewelry. In Russia, gold lies in the Urals and in Eastern Siberia.
In Canada, South Africa, Australia. Since gold is found in small quantities in nature and its extraction is associated with high costs, it is considered a precious metal.
Platinum (from Spanish Plata - silver) - is a precious metal from white to steel-gray. It is distinguished by refractoriness, resistance to chemical influences and electrical conductivity. It is obtained mainly in placers. It is used for the manufacture of chemical glassware, in electrical engineering, jewelry and dental medicine. In Russia, platinum is mined in the Urals and in Eastern Siberia. Abroad - in South Africa.
Gemstones (gems) - are mineral bodies with a beauty of color, luster, hardness, transparency. They are divided into two groups: stones going to the cut, and ornamental. The first group includes diamond, ruby, sapphire, emerald, amethyst, aquamarine. The second group includes malachite, jasper, and rock crystal. All gemstones are usually of magmatic origin. However, pearls, amber, coral are minerals of organic origin. Gemstones are used in jewelry and for technical purposes. In Russia, precious stones are mined mainly in the Urals, and abroad - in Brazil, India, on the island of Madagascar.
Coal - is a combustible sedimentary rock of plant origin with a carbon content of up to 97%. It lies in layers, the thickness of which sometimes reaches several tens of meters. Coal is one of the most important fossil fuels. It is used in metallurgy for the production of pig iron, as a raw material for the chemical industry, as a fuel. A variety of coal is coking coals, which are easily sintered and used in ferrous metallurgy. Coal with a high calorific value (8000 kcal/kg) is called anthracite. It is black in color and has a metallic luster. It lies between the layers of sedimentary rocks. Anthracite is used as a high-quality fuel. The main coal deposits in Russia: Kuzbass, Pechorskoye, Tunguskoye, Irkutskoye, Lenskoye, South Yakutskoye, Zyryanskoye, Appalachian (USA), Upper Silesian (Poland), Ruhr (Germany). The leading place for coal mining in the world is China. Coal is mined in the UK, in France, and in other countries.
Oil - a combustible oily liquid, usually dark in color, lies among porous sedimentary rocks, impregnating sands and limestones. It consists of a variety of hydrocarbons. Most scientists suggest that oil is the product of a change in organic matter. Oil is widely used as a high-quality fuel (its calorific value is 11000 kcal/kg), a raw material for producing gasoline, kerosene, paraffin, lubricants, and it is also a raw material for the chemical industry. In Russia, oil is produced in the West Siberian basin (almost 2/3 of all Russian production), in the North Caucasus, in the Volga region, in the north of Sakhalin Island. Abroad: in the Gulf countries, Algeria, Libya, Indonesia, Venezuela, the USA, Mexico, and other countries.
Natural gas - gases that can burn; found in the voids of rocks, sometimes forming large gas accumulations. Most industrial gas fields are associated with oil, but there are also independent fields. Natural gas reserves sometimes reach hundreds of billions of cubic meters. The richest deposits of natural gases are Russia, Ukraine, Saudi Arabia. Natural gas is the cheapest and most convenient fuel.