It's normal that the color is not written on Nanyang Jinzhu appraisal certificate, because different testing institutions have different appraisal standards for pearls. This certificate only measures the size, weight and growth texture of pearls, but personally, it is not very rigorous, because the golden Edison also has growth texture after amplification, so it may be impossible to distinguish Edison Golden Beads from Nanyang Golden Beads.

Laws and regulations:

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.