Jade have been used and loved by Chinese culture for thousands of years. With its unique coloration and luster, and its keen radiance, it gradually evolved into a symbol of power, status, wealth and holiness. Their smooth surfaces and flowing lines, immense variety of forms, colorful, exquisite luster and painstaking attention to detail are fascinating.
Mineral Ingredients of Jade
Jade is applied to 2 different rocks. One is Amphibole mineral which is also named Nephrite. The other one is Pyroxene mineral named Jadeite. Jadeite is Jadeitite. It is the Pyroxene consisted of Si, Ha, Al and Na. It is formed as crystallization from rocks, usually appeared with Glaucophane Schist, Muscovite, Lawsonite, Aragonite and Quartz. Jadeite has a Mohs hardness of between 6.5 and 7.
History of Jadeite
During Ching Dynasty, Jadeite were tribute payment for imperial court at first, then become popular to civilian. Most of Jadeite antiques and ornaments we saw today are from Ching Dynasty. In the Chinese culture, the Jadeite was considered the most noble of all gems. It is regarded as a propitious jewelry. It is also a hottest item in international auctions. Till today, Jadeite is still considered a precious gem with specific culture characteristic in East Asia.
The Enhancement and Treatment of Jadeite
Jadeite which from being in the rough to become a jewelry has only undergone the process of mechanical cutting, grinding, and polishing. Its texture and color are natural with no any enhancement or treatment.
Increasing temperature can accelerate the oxidation process which causing the color to change, for example: change the yellow or brown jadeite to bright red one. This color change may result in the jadeite more intense or of a different color.
Jadeite ore usually accompanies by other minerals, however, these foreign minerals normally appear as a stain or color spot which reduce the beauty. Bleaching is a traditional technology which soak jadeite into plum juice, fruit acid or hydrochloric acid to remove impurities and inclusions. After bleaching, the green color remains, moreover, the jadeite look nicer.
- Bleaching and Waxing
Place the jadeite in mild acid for a short time to remove surface inclusions and enhance the appearance of stone. In this process, the acid leaves small etch marks on the surface, however, the internal structure still remains undamaged. After bleaching, the jadeite is soaked with wax to make up all etch marks caused by acid.
- Bleaching and Polymer-impregnating
Place the jadeite in strong acid for a long time to remove surface inclusions and internal impurities. As the result, leaving the jadeite more transparent, however, the internal structure of jadeite is damaged and become brittle in this treatment. So it needs to be impregnated with polymer to strengthen its structure.
Generally, the more saturated the color is, the more valuable the jadeite will be. However, much of the jadeite ore is white so jadeite could dyed to produce a more desirable color. During this process, jadeite has been placed in chemical dye to artificially color the stone.
Used to improve luster and make up surface pits or etch marks. Place jadeite into liquid wax for a while then wipe it with a dry cloth to reveal the best luster of jadeite.
- After polishing, there are still some small pits remain on jadeite's surface which can be discerned with magnifier, even though it seems shine as mirror. Through waxing, some pits of the jadeite are infiltrated by wax and this process make the polished surface much smoother.
- Waxing has also been used to cover carved grooves which hard to polish.
- In the bleaching process, the acid leaves etch marks on jadeite's surface so to cover that the jadeite is subsequently soaked with wax.