When buying gold jewelry, always look for the karat mark. If all other variables are equal, the higher the karat, the more expensive the piece is. In the United States, 14-karat gold, or 583 parts pure gold, is the most common degree of fineness. Gold Karat less than 10k cannot legally be marked or sold as gold jewelry in the U.S. ¬†Always look for the karat mark or “k” that appearson the back of the piece. By U.S. law, if a karat mark appears you should also see the manufacturer’s trademark to assure you that the karat markingis accurate. The country of origin should also appear. In addition to the karatmark, every piece of gold jewelry should be stamped with a hallmark or trademarkof its maker, and sometimes its country of origin. These designations assure you that you are buying genuine karat gold jewelry.