Jewelry appraisal certificate is a public trust certificate issued to the authenticity and attributes of rare precious metals, precious stones or jewelry products, which is implemented by professional institutions and professionals who meet the appraisal qualifications.
About jewelry certificate:
Domestic certificates: NGTC, NGTC, GTC, GDTC, GIC.
NGTC, the National Gemo Logic Training Center and the National Jewelry and Jade Quality Supervision and Inspection Center, is usually referred to as the prefix of "National Inspection". Domestic diamond testing is the first choice, and other jewelry and jade can be tested. Strict standards, domestic certificate is preferred. For example, some destructive tests are needed on amber samples. Compared with other domestic institutions, the fees will be higher and the time will be slower.
NGSTC, National Gold and Silver Products Quality Supervision and Inspection Center (Nanjing), another testing center of national prefix. Not many people use NGTC. NGTC national inspection offices are only available in Beijing, Shanghai, Guangzhou, Panyu and Shenzhen. Elsewhere, manufacturers sometimes choose NGTC (available in several wholesale markets) if they want to issue national certificates.
Guangdong GTC Jewelry, Jade and Precious Metals Testing Center. The testing center with the largest amount of jadeite jade detection, because the four major processing bases of jadeite jade are all in Guangdong, the number and types of testing samples in Guangdong Province are unmatched by other institutions. The most common mass sales inspection organization in jadeite jade is extremely efficient and meets large-scale commercial applications. The polishing powder and wax impregnation of jadeite are very strict, which is quite certain in the industry.
GDTC, Guangdong Gold and Silver Jewelry Testing Center, is also a common certification body in the wholesale market and one of the certification bodies established by Taobao to test the quality of gold and silver products. The polishing powder standard of jadeite is slightly looser than GTC. Some jadeites with a small amount of polishing powder residue can be issued with A certificate, but the remarks will indicate that there is polishing powder residue there.