Method for identifying Jadeite
1.Characteristics of Jadeite
A Refractive Index:1.65 – 1.68
B Weight value:3.30-3.34
C Mohs hardness:6.50 – 7
Non-destructive (instrument identification):
(A)Identification dyeing
Can use Dow filter and Spectrometer to identify whether jade parts are stained.
1 Dow filter:
Dow filter allows red and orange light to pass through, under the filter the color of jade does not change to indicate no staining. If the green of the jade changes to red under the filter, it has been stained.
2 Spectrometer:
Observe the natural green jade under the spectrometer and have several young lines in the red absorption area: but the red absorption belt of the dyed jade appears with a rented absorption belt.
(B) Identification of high polyester compounds:
(high polyester compounds including resins, gels, etc.) can be tested for ultraviolet fluorescence and infrared spectrometers.
1 Ultraviolet fluorescence reaction:
The light emitted by ultraviolet lamps is divided into long and short waves. Most natural jadeites have no fluorescence reaction..If the natural jade contains impurities, there will be a weak powder outside lamp under the light of a strong powder white (blue) fluorescence reaction.
2 Infrared spectrometer:
Infrared accurately detects whether jade is injected with high-polymer compounds. The identification center will use the above non-destructive identification procedures to test the jade handed in by the guest, the object is natural jade or chemically treated, injected with high polyester compounds of jade or dyed jade (i.e. jade industry called B or C goods).
Destructive
Destructive identification method is only used in the research room, the general laboratory will not use this method to identify the guests handed over jade.
Destructive identification methods are:
(A)Heating
(B)Dissolving
(A)Heating method:
natural jade heat resistance of 900 degrees Celsius 1000 degrees Celsius.If it’s genuine, it turns brown at 400 degrees Celsius.
(B)Dissolve method:
Because jade contains high polyester (glial), its structure is loose, so poor solubility, just soak jade with a solution that dissolves high polyester, you can dissolve high polyester, and jade will become opaque gypsum.The above applies only to academic research, and these methods are not used in general accreditation.
The above applies only to academic research, and these methods are not used in general accreditation.
香港九龍翡翠珠寶鑑定中心有限公司 ● 版權所有 ● 不得轉載 Copyright © 2011 Hong Kong Kowloon Jade & Jewellery Laboratory Ltd. All rights reserved.