"MA" is actually "CMA", which is the English abbreviation of China Metrology Certification. It is a comprehensive certification and evaluation of the testing ability and reliability of testing institutions by the metrological administrative department of the people's government at or above the provincial level. This symbol is a basic qualification that any unit that issues a jewelry appraisal certificate must have.

"CNAS" is the abbreviation of China National Accreditation Committee for Conformity Assessment, and it is the national accreditation symbol of China Laboratory. The use of CNAS marks indicates that the laboratory has passed the relevant accreditation of China National Accreditation Committee for Conformity Assessment.

Extended data

At present, there are about hundreds of jewelry quality inspection institutions in China, and thousands of quality inspection certificates have been issued. The signs on the certificate are California and ILAC.

"CAL" is the abbreviation of China accredited laboratory, which is the symbol of examination, approval and authorization. Having CAL is mainly because the inspectors, testing instruments, testing basis and methods are qualified. The appraisal certificate with this logo has authority and legal effect.

"CNAS" is the abbreviation of China National Accreditation Committee for Conformity Assessment, and it is the national accreditation symbol of China Laboratory. The use of CNAS marks indicates that the laboratory has passed the relevant accreditation of China National Accreditation Committee for Conformity Assessment.

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People's Network-Jewelry Appraisal Certificates are mixed. Who will appraise the Jewelry Appraisal Certificate?