According to the Regulations and Naming Methods of Precious Metals in Jewelry (GB 11887-2008) implemented on June12009, gold and its alloys have six purities.

9K stands for gold purity of not less than 375%.

14K is not less than 58.5%.

18K is not less than 75.0%.

22K is not less than 9 1.6%.

Pure gold is not less than 99.0%.

Thousands of gold is not less than 99.9%.

The theoretical purity of 24K is 100.0%.