1, CMA is the abbreviation of China Metrology Certification.
CMA is the statutory compulsory certification of testing institutions by the state, and it is a sign that testing institutions are qualified in metrology certification. This sign shows that the testing organization is legal, with qualified testing equipment, personnel qualifications, workplace, testing conditions and sound management rules and regulations. Among them, CMA is the basic requirement of national laws for testing and inspection institutions. As long as it is a certificate issued by a formal appraisal institution, you can see this sign.
2.CAL stands for China accredited laboratory.
CAL mark is a special mark of qualified inspection institutions established or authorized by quality and technical supervision departments according to law. Examination and approval means that CNCA and local quality inspection departments confirm whether the inspection institutions have the ability to undertake market supervision and inspection of government departments according to the provisions of relevant laws and administrative regulations. The quality inspection established in the technical supervision system according to law is called "examination and acceptance", and the inspection institutions in the industry are called authorized according to law, collectively referred to as "examination and approval", using cal logo.
3.CNAS is the abbreviation of China National Accreditation Committee for Conformity Assessment.
CNAS marks represent that the inspection organization has passed the examination and approval organized by China National Laboratory Accreditation Committee. It shows that it has the technical ability to carry out testing and calibration services according to the corresponding recognized standards; Enhance market competitiveness and win the trust of government departments and all walks of life; It is recognized by the recognized institutions of countries and regions that have signed mutual recognition agreements.
Have the opportunity to participate in bilateral and multilateral cooperation and exchanges recognized by international conformity assessment agencies; CNAS National Laboratory Accreditation Mark and ILAC International Mutual Recognition Joint Mark can be used within the scope of accreditation; Be included in the list of authorized institutions to raise awareness. According to the relevant agreements of China's accession to the WTO, the "CNAS" logo can be recognized internationally, and has been recognized by the United States, Japan, France, Germany, Britain and other countries.
Therefore, when looking at the appraisal certificate of the jewelry you bought, you should pay attention. If you don't have the above three marks on your certificate, it basically means that the certificate has no credibility and the jewelry is more likely to be forged. Pay more attention when buying jewelry, and don't be cheated.
Extended data:
In addition to the above-mentioned nationally and internationally recognized marks, the jewelry appraisal certificate shall also include the following contents:
1, diamond grading certificate: the most important thing is to pay attention to the color grade and clarity grade of diamonds, and the big certificate of loose diamonds also has the diamond cutting ratio.
2, precious metal jewelry purity inspection certificate: the most important thing is the type of precious metal and its metal content.
3. Jewelry and jade appraisal certificate: the inspection conclusion is the most important, that is, the name of the gem.
According to national standards, natural jewelry and jade are no longer marked with the word "natural", but must be clearly marked with artificially processed or synthetic gems, such as:
A, the conclusion is "amber (beeswax)", indicating that this beeswax is a natural output;
B. "Synthetic amber" means that amber is not naturally produced, but is synthesized in an artificial laboratory.
C. "Plastic" means that amber is not naturally produced, but the product of artificial imitation of other materials.
In addition, there are descriptions of samples (color, shape, weight) and identification data (density, refractive index, absorption spectrum, magnification inspection, etc.). ), which is also essential information on the certificate.
4. "Remarks" column
Generally, some special samples will be encountered in the test process, which will be explained and noted in the remarks. For example, in the jade appraisal certificate, once colorless oil optimization is involved, it is obvious that purity optimization will be indicated in the remarks; Remarks column can also be the commodity name of the sample, the matching stone type of the finished jewelry and so on.
5. Standard
All the above contents must meet the following standards, and indicate the source of its identification basis on the certificate:
GB/T 16552 name of jewelry and jade
GB/T 16553 jewelry and jade identification
GB/T 16554 diamond classification
GB/T 18043 nondestructive testing method for precious metal jewelry content-x-ray fluorescence spectrometry.
GB/T 1 1887 specification and naming method of the purity of precious metals in jewelry.
Step 6 sign
In addition, the certificate must be signed by more than two appraisers (mostly handwritten). Very few testing institutions are signed by machines, such as the verification and testing of certificates issued by the Jewelry Testing Center of Geological University.
References:
Jewelry Appraisal Certificate-Baidu Encyclopedia