Gold Carat Explained

Carat is a measure of purity out of 24. Pure gold is 24 carat. 22ct is 22 parts gold to 2 parts alloy, 18ct is 18 parts to 6, and so on down to 9ct.

Carat for gold purity is a different thing from carat for diamond weight. The two share a name and nothing else.

Lower carat means harder metal and a paler colour. Higher carat means more gold, more value per gram, and a softer piece.