If you’ve ever purchased a piece of solid gold jewelry, there’s a good chance it has a “K” in its description.
The “K” in 10K, 14K, and 18K gold is short for “karats,” which is a measurement for the purity of gold. Pure, or 100% gold, is 24 karats. Gold is a very soft and malleable metal, however. Pure gold is unsuitable for jewelry as it can easily lose its shape and/or cause gems to get lost.
To make gold strong enough for jewelry, it is often mixed with other metals to form an alloy.
The purity of gold in a particular alloy is measured in number of karats. This is the “K” you see on the description of a jewelry piece.
10K, 14K, and 18K gold are standard alloys with varying amounts of gold.
- 10K gold = 41.5% gold
- 14K gold = 58.5% gold
- 18K gold = 75% gold
585, 750 Stamps
585 and 750 stamps denote 14K and 18K, respectively.
They correspond to the percentage of gold in each alloy.
The industry only permits 14K and 18K jewelry to be stamped.
How About 8k Gold?
If you’re on a budget but would really like a solid gold jewelry piece, 8k gold might be the material best suited for you.
The reason we don’t include it in our list of standard alloys is because it is not usually considered a standard alloy in most countries.
In the US, the lowest number of karats that can be legally traded as solid gold is 10K. In other countries like Germany, it is 9K.
8K is still a gold alloy, and a good material for jewelry in itself.