18K

"18K" refers to gold that is 18 karats, meaning 75% of the metal is pure gold and 25% is other alloys like copper or silver. Pure gold is 24 karats but is too soft for many jewelry applications. By blending gold with other metals, 18K gold offers a good balance of durability, appearance, and value. It has a rich, warm color and is popular in fine jewelry. The "18K" mark assures buyers of the gold's purity, indicating it contains 75% pure gold by weight.