gold
It is a type of expensive metal. Its color is bright yellow. It is a soft element with little corrosion. It is one of the densest chemical elements. It has been used from ancient times until the present day in the manufacture of jewelry and jewelry. It is called yellow gold. Gold is usually mixed with copper or silver in proportion. It varies, as the percentage of gold decreases, the shine of the jewelry decreases. It is also used in dentistry because it is characterized by its softness and resistance to corrosion. It has also been used in the field of medicine in treating rheumatism and osteoarthritis, and gold rays have been used in treating cancer. Among its uses is the manufacture of coins, just as the Pharaohs used it in the manufacture of Coffins, carts, and masks. There is another type of gold called white gold, which is gold mixed with tin or palladium.
Gold in nature
Gold is found in nature in the form of grains, either in rocks, the ground, or the bottom of rivers. It is often found with copper or lead and mixed with them. Gold may be found mixed with other minerals such as stibnite, cuprite galnia, tetrahydrite, sphalerite, arsenopyrite, tourmaline, and it decomposes. These minerals interact with weather factors, and this leads to the accumulation of gold in surface sediments, thus facilitating its extraction and discovery. Some rocks contain gold, which is found between pieces of rock or in the soil and is transported by rivers or torrents to be deposited at the bottom of rivers or on their shores, or it collects in outcrops in the form of grains. Round in shape, gold has been found on the banks of rivers in California, Western Australia, and the Ural Mountains, and is also found in Australia in the form of a large block.
Read also:How are diamonds formed?Many people search for gold with the aim of getting rich, so they search in valleys and water courses, but finding it is not easy because it is found inside rocks or mixed with other metals, and sometimes it is very pure and does not require treatment.
Methods of extracting and purifying gold
Gold is discovered in tunnels or underground using modern devices that find it hundreds of kilometers away. After digging, it is found and transported to laboratories and treated chemically, or ground until it completely turns into sand and then separated from the rest of the rock types. The method of extracting it depends on The size of the sample, the type of minerals mixed with it, their percentage in the sample, and the methods of extracting it:
- Using modern technology to separate gold from dust and other impurities by exposing it to strong water currents in a sieve, so the dust and impurities disappear and the gold remains.
- The use of mercury in separating gold by dissolving the gold and then ridding it of mercury through the distillation process.
- Cyanide, dissolution, or electrolysis method.
