The difference between 10- and 14-karat gold is the ratio between pure gold and non-gold alloy. The higher the karat rating, the purer the gold is.
If a metal is 24-karat gold, it’s entirely pure, unalloyed gold. All other karat indicators denote the percentage of gold to alloy out of 24 parts. Fourteen-karat gold is slightly more than 50 percent pure, while 10-karat gold is slightly less than 50 percent pure.
Ten karat gold is the minimum concentration that jewelers can market as gold jewelry in the United States. Fourteen karat gold is generally the standard for American jewelry makers. High-end gold jewelry in Europe and the United States is often made from 18-karat gold. Higher karat gold, such as 21-karat gold, has a brilliant yellow color and is popular throughout parts of Asia. Twenty-four-karat gold is not very practical for use in jewelry because pure gold is very malleable.