On the Pingzhou side of Foshan, GID Emerald Laboratory can produce it, which is the place of origin+classification, and the price is 300 yuan, which supports mailing for inspection; Pingzhou's quality inspection skills can also be developed. The appraisal certificate is marked with "enterprise name", which may be almost authoritative. I don't know if I can mail it.
NGTC, National Logic Training Center, National Jewelry and Jade Quality Supervision and Inspection Center, carries what we usually call the prefix "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.
Gtc certificate is a national inspection. Gtc certificate is the abbreviation of National Jewelry and Jade Quality Supervision and Inspection Center and National Gem Monitoring and Training Center. The third letter "c" also stands for certificate.
The National Jewelry and Jade Quality Supervision and Inspection Center is what we often call "National Inspection", which is abbreviated as NGTC in English. Jade can identify the authenticity and whether it has been artificially treated. Because it is the most authoritative jewelry testing institution in China, the appraisal fee is higher than that of ordinary institutions.
At present, there are three kinds of most common jadeite appraisal certificates in the market, namely, national inspection, provincial inspection, universities and third-party inspection institutions. The State Inspection is affiliated to the Jewelry and Jade Jewelry Management Center of the Ministry of Land and Resources. It is the maker of China's jewelry industry standards and the most authoritative testing institution, referred to as NGTC.