What does 916 gold mean?
916 refers to fineness: 916 parts of pure gold per 1,000 parts of metal, or approximately 91.6% gold purity. It is the millesimal equivalent of 22 karat (22 ÷ 24 = 0.9166…), so "916 gold" and "22K gold" describe the same alloy. The remaining 8.4% is typically copper and silver, added to make the metal hard enough for daily wear.
Hong Kong jewellery shops sell mostly 足金 (Chuk Kam, "full gold") of 999 fineness — effectively 24K — rather than 22K/916. Chains such as Chow Tai Fook and Chow Sang Sang post a daily gold price and charge workmanship on top.