Gold Purity Guide: 24K, 22K, 21K, and 18K Explained
Gold purity is measured in Karats (out of 24 parts) or Millesimal Fineness (parts per 1,000). 24K gold is 99.9% pure (Gold 999), 22K is 91.67% pure (Gold 916), 21K is 87.5% pure (Gold 875), and 18K is 75.0% pure (Gold 750). The higher the karat, the higher the pure gold content and monetary value.