Usually used to make jewelry, jewelry is marked with G 18K, AU750 or AU 750, 750 to indicate the gold content, and Au and G are synonymous with gold, that is, the gold content is18k =18 * 4.166% =
The "k" of K-Gold is a foreign word "Karat", which is expressed as follows: Karat gold (K-Gold). The measurement method of K gold is pure gold 24k (that is, 100% gold content), and 24K gold is pure gold, but it is impossible to have 100% gold content in reality, so the content stipulated in China is 99.
Extended data
750 gold has many colors, such as white, rose gold and yellow. If the proportion of silver is high, the color of 750 gold will be blue, and if the proportion of copper is high, the color of 750 gold will be purple, which shows that 750 gold has many different colors and high hardness compared with gold.
Because other precious metals are added to gold, 750 gold has relatively high hardness, rich colors and low melting point. It is characterized by high hardness, strong ductility and rich colors, which is very suitable for making all kinds of jewelry.
The hardness and toughness of 750 gold are higher than that of platinum, and it can maintain stable performance in various environments, is not easy to wear and deform, and can give a firm protection to diamonds. Therefore, it can be flexible in setting styles, and various complicated and fashionable styles can also be well set with diamonds, so it is often used to match the setting of diamonds.
Baidu Encyclopedia -G750
Baidu encyclopedia-18K gold