South Africa Gold Mines
Essay title: South Africa Gold Mines
The value of gold and diamonds and is of course a result of its rareness and also of its interesting physical characteristics. Gold is a so-called precious metal, which means it does not rust at normal conditions. It is resistant against many acids and a good electric conductor, which makes it useful for electronic circuits. Gold is also useful for jewelry because it will not change colors and tarnish.
Gold is normally found in pure form. This means it is not oxidized and it is not necessary to process it very much. But the amounts of pure gold are typically very little as it is normally evenly distributed in the rock. There are several geologic processes, which accumulate gold; most important for classic gold fields is erosion. The rock is eroded; the gold remains, and the small pieces of gold are washed into the next stream. But gold is very heavy, and so it tends to deposit in holes on the ground of rivers, a deposit called placer.
Other deposits are polymetallic deposits, where hydrothermal processes, often in combination with sulfuric chemical reactions, deposited large amounts of different metals in submarine depressions or in clefts. Typically gold is the rarest metal in the ore, but depending on the percentage and the value, it may be the most valuable part. As it is rather easy to process those ores in furnaces and separate the different metals, those deposits are mine since the early Middle Ages. Gold is found all over the world. It is part
of any volcanic eruption, though in very small amounts. Depending on the geologic situation, the mining is very different. Modern techniques and the massive use of machinery allow the processing of low grade ores with only very small amounts of gold, some Grams per ton. The most important gold producer of the World is South Africa.
The first South African gold rush followed the first diamond strikes by only a few years. Mining started