It’s Pure! The metals contain no additives or alloys to detract from its natural beauty. Gold is commonly known in karat weights of 22, 18, 14 and 9. To achieve these various karat weights, another metal is added or “alloyed” to the gold, diluting the purity of the metal. For example, 18K Gold is, by weight, only 75% gold with the balance being some combination of silver, copper or palladium.