GIA is an American Gemological Institute with a global scale comparable to IGI, which was first established in the United States in the 1930s. But the real large-scale development was in the 1950s, which happened to be the period of great development of American industry and consumption. Therefore, there is an urgent need for a unified standard that can be replicated on a large scale to meet people's large demand for diamonds. Therefore, GIA prospectively summarized the previous experience, put forward the concepts of "clarity" and "color" used by merchants in the industry before, and formally put forward the 4C statement in the 1950s, which played an important role in the rapid development of the jewelry industry in the future, and in the following time, it also introduced many instruments for analyzing gems, which facilitated the insiders to identify gems more efficiently. It can be said that American Gemological Institute was an early promoter of the standardization and popularization of jewelry industry to the public. Its positioning has always been loyal to serving the middle class with the most consumer confidence and the largest number. Therefore, GIA has many fans in the United States, and relatively speaking, high-end jewelry in Europe is used less. What we don't know is that although GIA is a non-profit organization, most of its funds are sponsored by major jewelry companies in the United States. The appearance of its certificate is also in line with the development interests of American jewelers, and it also provides identification certificates for many consumer brands facing the public. For example, the famous American online shop "Blue Nile" focuses on mainstream middle-class men, and basically uses GIA and AGS certificates. When Tiffany took the middle-class route, she used a lot of certificates from American Gemological Institute. With the deviation of self-positioning and brand marketing from GIA mass positioning, I began to use my own certificate.

GIA certificate emphasizes unity. There is a sense of standardization like an assembly line. From the page of the certificate, the star's jewelry and the goods in the street shop all use the same plate making and design. GIA India, GIA America and GIA Hong Kong can't tell their different distribution places. Just like McDonald's and GAP in America, they are the certificates of every teacher, fisherman and worker in the world. Therefore, it can be said that American Gemological Institute meets the consumption needs of most people in modern industrialization. At the same time, in China, with the reform and opening up, GIA certificate also entered the China market with the influx of American diamonds in the 1990s, becoming one of the international certificates with high recognition in China.

Note: GIA certificate is recognized as the most authoritative and objective appraisal certificate in the world. In contrast, the authority and appraisal standard of IGI certificate is looser than that of GIA. Among the diamonds of the same grade, those with IGI certificate will be 3-5% cheaper than GIA.