The Metal Series Pt. 1 – Gold Purity

Jewelry is the most common reason consumers own gold today.

About 78% of gold consumed each year is made into jewelry. It has been one of the primary uses for the metal, because of its beauty and durable properties.

There are 2 main systems for measuring the purity of gold. The most commonly used in the United States is the karat system. Karats express the purity of gold in fractions of 24. For example: Pure gold is denoted 24 karat gold or 24k, all 24 parts are gold. Gold purity is also measured using the millesimal fineness system. This system denotes the purity of gold alloys by parts per thousand of pure metal by mass in the alloy. For example: A gold alloy containing 75% gold is denoted 750.

The process of alloying or mixing other metals with pure 24k gold creates a harder more durable metal alloy, and can also change the color. The types of metals commonly used are nickel, palladium, copper, zinc, and silver.

If an item is stamped:

18K or 750 – it is 18 parts gold & 6 parts other metals
14K or 585 – it is 14 parts gold & 10 parts other metals
10K or 417 – it is 10 parts gold & 14 parts other metals

The legal standard is to stamp all gold jewelry with the metal purity. The minimum purity to be called gold jewelry varies by country, and is 10k in the United States.

See you on our next installment of the Metal Series brought to you by!