The carat or karat (symbol/abbreviation K) is the unit used to measure the purity of gold.

Pure gold (24K) is soft, malleable, and highly valuable. Because of its softness, it is not commonly used for everyday jewellery.

Gold is usually mixed with other metals such as silver, copper, or zinc to create stronger and more durable alloys suitable for jewellery production.

• 24K – Pure gold.
• 22K – Contains 22 parts pure gold and 2 parts other metals. Gold purity is 91.7% (22/24).
• 21K – Contains 21 parts pure gold and 3 parts other metals. Gold purity is 87.5% (21/24).
• 18K – Contains 18 parts pure gold and 6 parts other metals. Gold purity is 75% (18/24).
• 14K – Contains 14 parts pure gold and 10 parts other metals. Gold purity is 58.3% (14/24).
• 9K – Contains 9 parts pure gold and 15 parts other metals. Gold purity is 37.5% (9/24).

In Türkiye, especially in Istanbul’s Grand Bazaar and jewellery markets, 22K gold jewellery is traditionally very popular for weddings, gifts, and investment purposes. Younger buyers and international customers often prefer 18K gold because of its modern designs and durability.

Türkiye also uses the “millesimal fineness” system to indicate gold purity. This system shows the amount of pure gold in 1000 parts of alloy. For example:

• 24K = 999
• 22K = 916
• 21K = 875
• 18K = 750
• 14K = 585

These fineness numbers are commonly stamped on gold jewellery as official hallmarks in Türkiye.