K gold refers to the alloy in which gold and other metals are mixed together. 24k gold and 18k gold are gold jewelry, which can be divided into different kinds of K gold according to the gold content in jewelry. 24K does not exist, and 99.9% of the underlying gold is also called thousands of gold. Because the gold content of 18K gold is 75.0%, it is also called 750.

At present, pure gold is the highest purity in the market, but it is generally used as pure gold jewelry because of its soft texture and easy deformation.