(1) Appraisal Standard of Hetian Jade of AQSIQ

Hetian jade identification is based on national standards GB/T 16552-20 17 "Jewelry and Jade Name" and GB/T 16553-20 17 "Jewelry and Jade Identification" (these two standards were published on 20 18 1 instead of version 20 10) and Xinjiang local standard DB65/T 035—2065, the detection of precious metal content in Hetian jade jewelry inlaid with jade also needs to be based on the national standard GB11887-2012 "Provisions and Naming Methods for Precious Metal Purity of Jewelry".

(2) Identification method of Hetian jade by the State Quality Inspection Bureau.

Including conventional gemmology and large-scale instrument identification methods. Generally, hetian jade samples are tested and identified by conventional gemological identification methods. If you can't draw an accurate conclusion, you need to further test and analyze the sample by large instruments, and finally get an accurate result. Conventional gemological identification methods include visual inspection (mainly color, shape, transparency, luster and special optical effects, etc. ), amplification test, refractive index and birefringence, ultraviolet fluorescence, mass, density and Mohs hardness, etc. The identification methods of large instruments include infrared spectrum analysis, ultraviolet-visible spectrum analysis and laser Raman spectrum analysis.

GSB16-3061-2013 includes six standard samples of Hetian jade, including white jade, sapphire, jasper, jet jade and sugar jade. In the inspection, Hetian jade samples should be classified according to the physical standard samples, especially the samples on the color dividing line, such as white jade, blue white jade and sapphire, which should be inspected by 2 ~ 3 nationally registered jewelry and jade quality inspectors with systematic training and experience, and finally achieve consistent results.

Hetian jade has white, bluish white, cyan, green, ink, sugar, yellow, two-color or multi-color. , oily luster, slightly transparent, hackly fracture, green varieties can see the cat's eye effect; Fiber interwoven structure; The refractive index measured in the laboratory is 1.6 1 (spot measurement); No ultraviolet fluorescence; The density is 2.90 g/cm3~3. 10 g/cm3, often 2.95 g/cm3. In the case of the same size, hetian jade is heavier than its imitation in most cases. Mohs hardness is 6.0~6.5, and the knife can't scratch it. Most imitations have low hardness, so knives can paddle. There are many similar products or imitations of Hetian jade in the market, such as xiuyan jade, quartzite jade, marble jade, chalcedony, glass and plastic. By observing the characteristics of color, structure and luster, it is easier to identify.