Copper plating 18K Gold means that the surface of jewelry is 18K gold, and copper is below the surface layer of 18K gold. 18K gold is an alloy with a gold content of at least 75%, that is, an alloy with a gold content of 18 / 24, and the remaining 25% is other precious metals, including platinum, nickel, silver, palladium, etc. 18K gold is a kind of gold jewelry with low cost and comfortable wearing.
In theory, 100% gold can be called 24K gold, but in reality there can be no 100% gold, so China stipulates that gold with a content of more than 99.6% (including 99.6%) can be called 24K gold.
These K gold contents are the general specifications of jewelry. According to the national regulations, gold jewelry lower than 9K cannot be called gold jewelry. Some gold jewelry is marked with text, which stipulates that the gold content is not less than 99%, and the gold content is more than 99.9%.
Gold plating is divided into two categories, one is gold plating with homogeneous materials, the other is gold plating with heterogeneous materials.
18K gold plating on copper is gold plating on heterogeneous materials. Gold plating of homogeneous materials refers to gold plating on the surface of gold jewelry. Its significance is to improve the brightness and color of jewelry.
Gold plating on heterogeneous materials refers to gold plating on the surface of non gold materials, such as silver gold plating and copper gold plating. Its significance is to replace the color of the plated material with the luster of gold, so as to improve the ornamental effect of jewelry.
The quality of gold plating depends on the thickness and luster of the gold plating layer.