14K gold and 18K gold represent the purity of gold, with 24K being more than 99.6% gold content, 18K being 75% purity and 14K being 58% purity. The higher the purity, the higher the price, the smaller the hardness of gold, and the easier it is to change color.

The biggest difference between 14k gold and 18k gold is the difference in gold content. The higher the content, the softer it is, and the lower the content, the harder it is. Therefore, the K gold used for setting gems is basically 18K gold and 14K gold. 18K gold is generally used in China, but 14K gold is preferred abroad. It is recommended to use 14K gold for particularly complicated styles because it is more stable.