Shanghai A is the Shanghai A-share trading market. K gold means that theoretically 100% gold can be called 24K gold, but in reality it is impossible to have 100% gold, so China stipulates that gold with a content of more than 99.6% (including 99.6%) can be called 24K gold. The gold content of 18K gold is the general specification of jewelry. According to national regulations, gold ornaments under 9K cannot be called gold ornaments.