Jadeite jade is a very porous stone. It comprises of very minute granules of monoclinic crystals inter-locked against each other. This creates a lot of 'spaces' and 'pores' in between the crystals whereby organic compounds can be force injected into the crevices. Hence, jade is an extremely good stone for enhancement and treatment such as waxing, dyeing and polymer impregnation.
When a small piece of jadeite jade is examined under an EPMA (Electron Probe Micro Analysis) equipment, which I have the opportunity to use at a geology department in a major university in my city, the resulting EPMA chart which is magnified 50,000x shows a cross-section of the jade piece like a mosaic tile floor with the cement in between. In this case the cement is the spaces in between each of the inter-locking crystals.
Jadeite Jade which has NOT been treated is known in the trade as Natural Type A Jadeite Jade.
Enhancement and Treatment: A vivid natural color jadeite jade with excellent translucency is a very rare piece of jade. Hence, jade 'manufacturers' often enhance a low grade jade piece to improve on its color, translucency and luster. The various forms of enhancement and treatment are:
Waxing
Dye Injection
Polymer Impregnation
Waxing: Waxing on the surface of a jade piece is not considered as a treatment as it is being accepted as a normal practice by international standards. The internal part of the jade piece has not being altered in any way. Waxing is not permanent. After a while the wax will wear off or it looks dull when in contact with a hot medium. However, you can send it back to your jade dealer for re-waxing.
Dye Injection: Dye injection has been used for many years. Usually spinach vegetable is used as it has a good vivid green and it is easily available. The pores of the jade pieces are preliminary washed in mild acid or plum juice to remove some of its surface impurities. Then it is pre-heated using a basin of hot water to open up the pores. The jade piece is then removed and soaked into vegetable dyes for about a week. On removing the jade piece it is dipped in wax to seal off the pores. Waxing will also add a good luster to the surface of the jade. And Presto! you have a good green jadeite jade. Nowadays this is not a common practice anymore as the dyes leak out easily. For some uncrupulous jade dealers who wanted a quick profit or to fleece tourists this practice is still prevalent.
Dyed concentration along the vein lines of a Type C Dyed Jadeite Jade
Polymer Impregnation: A more permanent method of treating a jade piece is to impregnate it with polymer. Polymer used is usually opticon as its Refractive Index is very close to jadeite jade. The method of impregnating polymer is almost the same except that higher technology is used and it is done on a mass basis. Once polymer is impregnated into a jade piece the jade will have a very good luster and translucency. Polymer impregnation came into practice in Hong Kong in the early 80s.
Method of Detection: A jade dealer who has been dealing in jade for many years may recognize a treated jade by sight. Dyed jade is quite easily identified under a 60x microscope where one can see the dye concentration along the vein lines. The color will look unnatural with green veins very obvious to the naked eye. Dye can also be detected by using a Chelsea filter where it will appear reddish. Dye jadeite jade is known in the trade as Type C jade.
Detection of polymer impregnation may be a bit difficult. Even with the naked eye an experienced jade dealer can deter it with only a 90% confidence. A thermal tester can be used to detect whether a jade piece has been impregnated with polymer. When the hot tip of the thermal tester is lightly touched against an inconspicious part of the jade a characteristic 'plastic' odor is given out. However, this method is seldom used as this is a destructive test when you have a polymer impregnated jade specimen.
FTIR Scan: A more advanced instrumentation equipment called the Fourier Transform Infra Red (FTIR) is needed. FTIR is used commonly to identify organic compounds. As a polymer is an organic compound the FTIR will pick up a unique signature fingerprint that will indicate that a jade piece has been impregnated. The FTIR equipment projects a high energy beam of IR through the jade specimen. The principle is simple. Polymers are hydrocarbons and if exposed to an IR beam the C-H bonds would vibrate, flex or bend. By mapping the results of the scan on a graph certain absorption peaks are indicated as spikes. Jadeite Jade has a certain characteristic 'bell' shape curve and certain peaks at specified wave-number will indicate whether a jade piece is natural or has been impregnated with polymer.
Jadeite jade which has been impregnated with polymer is known as Type B jade.
Thank you for reading this guide. If you find it useful please give me a 'Yes' vote. I will continue to share my knowledge of jadeite jade with all my customers as well as the whole community of ebay buyers and sellers.
Orignal From: Jadeite Jade Enhancement Treatment : How To Detect It
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