1, GIA (Gemological Institute of America) is an authoritative non-profit scientific research institution recognized by the industry and headquartered in California, USA. It takes the fair and authoritative 4C appraisal system widely used in the industry as a reference model, so this institution attaches great importance to maintaining its reputation in gem appraisal. The diamonds reported by GIA are more expensive than those reported by others in the same level. Therefore, the GIA report has been widely recognized by the industry and consumers. Besides GIA, the closest thing is AGS, which is also a non-profit organization. Its identification laboratory studied cutting earlier and more carefully than GIA. I remember that only the ideal cutting recognized by AGS was the real perfect cut.
2.IGI (International Gemological Institute): the "certificate factory" of chain jewelry stores in the United States and Canada, with large appraisal volume, high speed and low appraisal fee. However, when the stones they have identified are sent to GIA, the results are often different. The level of their laboratories in Belgium, Dubai, new york and LA is also uneven. The gem evaluated by IGI in Dubai has the lowest credibility, so the price is the lowest. Other major appraisal institutions: it is generally felt in the industry that other institutions. Most HRD reports are higher than GIA's and the performance results are more detailed.
3. The price of stones identified by 3.EGL is also much lower than that of Gia. China State Inspection: Appraisal is stricter than GIA, and consumers will suffer if they don't know the difference. EGL (European Gem Laboratory): This is a profit-making organization. Its nature is to make money, so the appraisal fee is relatively high. Generally speaking, GIA has five stars, IGI has five stars and HRD has five stars. There is nothing to doubt about that. Are international authoritative organizations.
Its ranking is also equivalent to the price of the diamond itself, so it has certain reference value.