At present, many gold ornaments are doped with metal iridium, and the real gold content is very low, so it is difficult to identify them by chemical methods, and it must be identified by professional instruments. Some fake gold ornaments are even more outrageous. They are just a mixture of copper and zinc, which will melt after being soaked in strong acid, so you can only buy fake gold at a high price, but not real gold at a low price. Don't be cheated. . .