10K – 41.7% 14K – 58.3% 18K – 75.0% 24K ... in the U.S., so if it's marked with 10-karat gold it has to be accompanied by a stamp that says who made that piece of jewelry, so they ...

By law, gold pieces are required to have a stamp that indicates how much gold is contained in the piece. The stamp will display a value such as “12k,” “14k,” and “24k,” and provides a ...

Other metals are not given a hallmark stamp in gold. Irregular percentage compositions ... and used to provide proof that the jewelry is of 14K, 18K or 22K.