Such a noble metal like gold rarely gets into human hands in its pure form. Usually those items that we call gold are actually alloys of gold and ligature. Ligature is called the admixture of base non-ferrous metals. These impurities, which are added to the alloy, are used to improve the operational and other necessary qualities, since this precious metal in its pure form is very soft. Pure gold is subject to severe abrasion, and products that can be made from it will be easily scratched and often torn.
Even in antiquity, scientists determined that the best ligatures for gold are silver and copper. Therefore, they began to be added to gold alloys in various quantities. And in order to be able to know the amount of ligature added to alloys for the manufacture of jewelry began to use gold samples. That is, in the modern jewelry world, the quality of any jewelry and products made of this precious metal does not depend on which (red or white) gold is used for its manufacture, but on the content of impurities in them, which give them strength and durability.
Most often, such jewelry is made from 585 gold samples. Among the material for the manufacture of jewelry distinguish red, yellow and white gold. Red gold is made by adding copper to it, this increases its strength and durability. Silver is usually used as a ligature for yellow, and nickel and palladium are added to the alloy to produce white. Historically, two systems for determining gold samples have been used — karat and metric. In Russia, the metric system is mainly used, based on the determination of the weight of the precious metal in thousandths of the mass of the product. Therefore, it is easy to figure out what gold samples are. For example, in 1000 grams of alloy 585 samples contains 585 grams of pure gold and 415 grams of ligature. A sample of white gold is likewise determined.
The carat gold sample determination system is mainly used in the UK, Europe and the USA. In this case, the designation is in carats. A carat is defined as one twenty-fourth of the weight of gold in an alloy. Therefore, pure precious metal has 24 carats, a sample of 750 corresponds to 18 carats, a 375 sample is already 9 carats. The most popular gold alloy in the world is 750. Almost any colored gold product is made using this gold sample. Differences in the color of jewelry are achieved by the fact that various precious metals are added to the composition of the alloys - palladium, iridium, rhodium, chromium and zinc.
Therefore, in the modern jewelry market there is a massive presence of blue gold, green gold, pink gold, black gold, as well as white gold. However, the most common are yellow and a combination of yellow and white gold. But in everyday life there are usually alloys of four samples: 375, 585, 750 and 958. Gold alloy 958 samples are most often used for the manufacture of works of art. There is another 900 test, which in many countries for minting gold coins and in dentistry. If jewelry is made of alloys below 375, then they are no longer considered jewelry, they are referred to jewelry.
In many countries of the world, in the manufacture of jewelry, the state exercises control over the content of gold in alloys. In some states, there is still additional control of jeweler corporations, which have their extremely complex and diverse brands. However, in some countries, such as Egypt, Turkey, the United States and South America, there is no government control over the manufacture of gold products.