YELLOW GOLD

Pure, 100% fine gold is 24 karat. This is a rich, deep golden color that has been used for jewelry historically but is too soft for general purpose jewelry. Here are a few notes about "karat gold":

18 karat gold means that the metal is 18 parts out of 24 pure gold, or in other words, 75% pure gold. The other 6 parts (25%) consists of an alloy of other metals.18 karat gold is the standard for European jewelry.
14 karat gold is 14 parts gold, or 58.5% pure gold. It is the standard for American jewelry.
In addition to the proportion of pure gold, the term "karat" is used to signify solid gold alloys versus gold platings or gold-filled pieces of jewelry.
Interestingly, each country has a minimum "karatage" for gold alloys that may be legally sold as gold. In the United Sates, the minimum is 10 karat gold. In France and Italy, for example, the minimum is 18 karat gold.