Nowadays there are a lot more and more treated jadeite and jadeite simulants in the market. Thus, it's very good to have knowledge of classification of jadeite by treatments, how to identify jadeite and have to be familiar with its popular simulants (imitations), especially for people who love jadeite jade.
By treatments, there are Type-A Jadeite, Type-B Jadeite, Type-C Jadeite and Type-B+C Jadeite in general. Moreover there are also Assembled Jadeite, Coated Jadeite and Fused-powder Jadeite in the markets.
Fig 1. Treated Jadeited Jade Dount Pendants
What is Type-B Jadeite?
Type-B Jadeite is bleached and polymer impregnated jadeite. It has been subject to acid bleaching to remove undesirable impurities and thereafter strengthen with polymer material before fashioning. First of all the rough jadeite is soaked in concentrated acids, such as sulphuric and hydrochloric acids, for days to weeks to remove the impurities. Low heat is also applied to intensify the corrosion process. Some bleached jadeite may be treated to another round of alkaline bath to loosen the grains. As this process leaves voids and fine gaps around crystal boundaries, the bleached jadeite becomes porous and brittle, called ‘chalky’ jade in trade, and polymer filler is then necessary to strengthen the bleached jadeite and to improve its transparency. If the bleached jadeite retains the original color, then only polymer is implied (Type-B jadeite).
There are many Jade & Jewelry shops as well as stores where you will be told that all are Natural Grade ‘A’ jadeite (jade), no treatment, no dye even though they are truly not Type-A jadeite. You may sometimes be told in a little bit honest way that this is genuine Grade ‘B’ Jade which means all impurities inside the jade have been suck out. The sale gimmicks will not tell you more. They may be trained by the unscrupulous dealers to tell the prospective customers how to explain what’s Type-B (or) Grade-B Jadeite Jade. Just to recap, when rough jadeite (very low quality) has been undergone bleaching treatment by acid, it becomes ‘chalky jade’ which means brittle and has neither natural jadeite structure nor value and then impregnated with polymer.
Fig 2. Treated Jadeite Jade (Grade B Jade) which is abundantly found at most of Jewelery Stores in Singapore [Do you notice the price they are selling for Treated Jadeite?]
What is Type-C Jadeite?
Type-C Jadeite is dyed jadeite. The process is performed to enhance green, lavender, yellow or red jadeite. Since jadeite is aggregate, dyeing agent can be introduced into the jadeite via the grain boundaries and surface reaching fractures. Prior to the dyeing process, the jadeite has to be thoroughly cleaned and subsequently heated to expand the grain boundaries before inducing the dyeing compound under vacuum to allow easier and thorough flow of dye into the jadeite. However Type-C is not common in today’s market as it is being replaced by Type-B+C jadeite.
What is Type-B+C Jadeite?
As the name implies, it combines both former treatment processes. The base material which lacks color has to be dyed during a polymer impregnation process. The color may be introduced separately or as a colored polymer.
Fig 3. Stall in China [photo credit :: Lau]
Treated jadeite jade are beautiful with pleasing colors but they are ephemeral. It will be valueless in time to come. So you are not buying a precious gemstone, you are only purchasing a costume jewelry to fit your present fashion trend. If you want a precious thing of value or if you are a keen believer that jadeite jade would bring you fortune and luck then you should avoid buying treated jadeite jade. Jadeite jade of this type can be bought cheaply at flea market or on 5-foot pavement along a busy street in China or Hong Kong.