AU750 necklace refers to an alloy necklace made of 75% gold and 25% other metals. In the jewelry industry, the purity of jewelry is expressed in carats (several thousandths), while AU750 represents that necklaces contain 75% gold. The higher the purity, the more precious the materials used, which makes this necklace belong to middle and high grade. This alloy has certain oxidation resistance and wear resistance, and keeps the luster and sense of value of gold itself.