Gold: There are 995 pure gold, 999 pure gold and 9999 thousand pure gold. Generally, as long as the purity of gold is above 99.5%, it can be called pure gold or 24K gold.

The hardness with low gold content is better, and the inlaid gems are not easy to fall off.

The gold content per potassium is 4. 166%,

18k = 18 * 4. 166% = 74.998%，

24k=24*4. 166%=99.984%

24K contains 99% gold and 22K contains 9 1. 7%, 18K contains 75. 1%, 14K contains 58. 5%, 12K contains 50%.

At present, the gold jewelry sold in the market is divided into pure gold jewelry and K gold jewelry. According to the national standard GB 1 1887, the contents of several common gold ornaments are as follows:

24K-At present, gold ornaments marked with 24k are occasionally seen in the market. According to the national standard, the theoretical value of 24K gold content should be 100%, and gold is barefoot. So strictly speaking, 24K doesn't exist. It is incorrect to mark 24k gold in sales, which does not meet the national standards.

Thousands of pure gold-the content is 99.9%, commonly known as three 9s.

Pure gold-the content is above 99.0%, commonly known as two 9s.

The content of 18k- is 75.0%,