Two of the most commonly used gold alloys are 10 karat (10K) gold and 14K gold. Both are combined with other materials to make the metal harder and make the most use out of the least amount of gold.
10K gold contains less gold than 14K gold. While 10K gold is 41.7 percent pure, 14K gold is 58.3 percent pure. Both are usually mixed with copper and silver.
An object made of 10K gold will weight less than an equal-size object made of 14K gold. This is because gold is heavier than other metals that are mixed with it and 14K contains more gold.
In appearance, 14K gold is deeper yellow than 10K gold. It also has more gold luster and shine.
Objects made of 10K gold usually cost less than those made of 14K gold, as 10K gold items contain less gold. Expensive gold objects tend to be made of 14K gold or finer.
Fine jewelry is predominantly made of 14K gold or finer, especially if it contains precious gems. However, 10K gold is often used for less expensive jewelry and larger gold objects such as flatware and tea sets.