Gold leaf is gold that has been hammered into extremely thin sheets and is often used forgilding. Gold leaf is available in a wide variety of karats and shades. 22-karat yellow gold is the most commonly used. Gold leaf is sometimes confused with metal leaf but they are different products. The termmetal leaf is normally used for thin sheets of metal of any color that do not contain any real gold. 24 karats is pure gold. Real yellow gold leaf is about 91% pure gold. Silver colored white gold is approximately 50% pure gold. Layering gold leaf over a surface is called gold leafing or gilding. Traditional water gilding is the most difficult and highly regarded form of gold leafing. It has remained virtually unchanged for hundreds of years and is still done by hand.