Among all kinds of jade jewelry appraisal certificates, the certificate issued by Geological University is the most authoritative. Other differences are not big, as long as it is a formal appraisal institution with a steel seal and a red label of the certification institution on the back.

NGTC certificate, National Jewelry and Jade Quality Supervision and Inspection Center, is a national professional quality inspection institution authorized by the relevant state departments according to law, and is the authoritative institution for jewelry and jade testing in China. It plays a guiding role in standardizing the domestic jewelry market and promoting the healthy development of the jewelry industry. GIC certificate, GIC is the abbreviation of English name of Jewelry College of China Geo University. GIC is a teaching and research unit focusing on jewelry education, the earliest and largest professional institution of gemology education and research in China, and one of the only three national pre-examination training stations for jewelry and jade quality inspectors in China. Rooted in the fertile soil of the national "2 1 1 project" key universities, it has now developed into a multi-level and multi-functional teaching and research institution for jewelry education, jewelry testing, scientific research and technology development, and has been praised as the "cradle of jewelry education" by jewelry circles at home and abroad.