1、GIA

The certificate of diamond appraisal issued by Gemological Institute of the United States proves that internationally renowned diamond appraisal institutions have laser codes consistent with the certificate on the waist edge of diamonds, which can also be inquired in official website. GIA diamond classification report and GIA diamond processing are considered as the first gem certificates in the world. Diamonds of all sizes are sent from all corners of the world to the college for analysis and classification.

2、IGI

The International Gemological Institute in Antwerp is the oldest gemological institute. 1975 has established laboratories in new york, Bangkok, Mumbai and Tokyo. The IGI Diamond Report is essentially a statement, which verifies the authenticity of diamonds with the help of a world-recognized system and provides reliable and correct diamond identity and grade.

3, goblins

Goblin is a world-renowned identification laboratory in colored gems with a long history. In the identification of gem processing, the identification of origin is in a dominant position. During the period of 1920s, Guberlin Company sent personnel to study gemology with the famous gemologist H.Michel at that time. After completing his studies, he brought back the most advanced knowledge and equipment of gem identification and established the Cooper Gem Laboratory.

4、GCGI

GCGI Certificate is the British Gemstone Color Classification Institute, and it is the first institution in the world to study colored gems classification. GCGI is a reputable non-profit organization, which is dedicated to the grading research in colored gems. Because of its rigorous, meticulous and complex analysis of gems, it is praised as a jeweler's certificate by the global jewelry industry and recognized by all countries in the world.

5、GRS

GRS is a famous private testing laboratory in Switzerland, which mainly tests the world's major gems. The commercial names of its gems: pigeon blood red, sapphire blue and cornflower are widely circulated all over the world. Enjoy a high reputation in the Asia-Pacific region. GRS is a gem appraisal institution founded by Dr. A. Peretti, a Swiss gemologist. Can independently issue test reports.

6、SSEF

SSEF, a well-known European laboratory, is generally used to identify pearls and high-end gems. The research institute was established in 1974, and its services include identification of gemstone varieties and places of origin, identification of natural and cultured pearls, and affairs consultation. The appraisal certificate can be provided in English, German and French according to the customer's needs, and the content is limited to the corresponding jewelry appraisal matters, and does not involve any commercial activities such as commercial appraisal.

Extended data:

CMA, CAL and CNAS are common in the certificate of jewelry and jade appraisal. According to reports, CMA is a sign that the measurement certification of testing institutions is qualified, and the institutions with this sign are statutory inspection institutions.

According to the relevant provisions of "People's Republic of China (PRC) Product Quality Law", the institutions engaged in social testing and inspection of products in China must be qualified by the national or provincial metrological certification management department in conjunction with the recognized institutions, and can only engage in testing and inspection activities after being established or authorized according to law.

CAL is the symbol of inspection institutions recognized by national quality inspection, and institutions with this symbol are qualified to make arbitration inspection conclusions. Having CMA mainly means that the testing personnel, testing instruments, testing basis and methods are qualified, and the premise of having CAL mark is that the measurement certification is qualified, that is, CMA qualification, and then the quality management conditions of the organization also meet the requirements.

It can be considered that the working quality and reliability of the mechanism with CAL are further improved than that with CMA only. CNAS was recognized by China National Accreditation Committee for Conformity Assessment. CNAS is a combination of CNAB, a former Chinese certification body, and CNAL, a Chinese laboratory, which supports international mutual recognition.

Any of the above three marks is valid, especially the first mark CMA, which is the basic requirement of national laws for testing and inspection institutions. Look at the test content. Including the name, color, purity, total mass, density, refractive index and other items of the goods submitted for inspection, these items are very strict in the nationally certified jewelry and jade testing institutions.

Look at the signature of the appraiser. The appraisal certificate must be signed by two appraisers to be valid: one is the appraiser and the other is the reviewer. In the meantime, I have to look at the seal. Strictly speaking, it should be a steel seal, and the font on it can be clearly recognized.

There is the serial number of this certificate on the back of the appraisal certificate, which should be consistent with the serial number posted on the back of the physical object. In addition, some certificates have numbers, which can be queried on the website or through SMS. If it is genuine, you can definitely find the style you bought by entering the number.

Baidu Encyclopedia-Jewelry Appraisal Certificate

People's Daily Online-False certificates of jewelry and jade emerge one after another. Experts teach you how to identify the authenticity of certificates with the naked eye.