Jewelry sold in the regular market now, especially high-grade jewelry, is generally natural stone, and most of them have been tested by relevant state departments, such as diamond jadeite, agate and crystal, which are all safe. There are also colored, discolored or synthetic gems, which are abundant in the second-hand market. Some fake gems are beautiful in color or luster, may be irradiated by gamma rays or neutrons, or contain corrosive substances. Be careful when wearing these fake gems. Generally speaking, colored crystals are mostly the result of radiation from radioactive materials in the stratum.