Abstract:
Researches on the field of the raw jadeite classification are rare.The traditional classifications were based on speculative guessing and gambling jadeite,according to the characteristics of different types of skins and arenaceous grains on the surface of raw jadeite.Taking the jadeite produced from bibbey-rock as an example,there are four types including white salt-like arenaceous skin,yellow salt-like arenaceous skin,red salt-like arenaceous skin and black salt-like arenaceous salt skin. In the recent years, the raw jadeite was sawed into two or more than two pieces, for trade in the Myanmar jadeite bid auction. The inner parts of the jadeites, such as colours and bases,could be observed straightforward. Through researches on the types of jadeites traded in Myanmar jadeite bid auction, the author has came up with a new classification of the raw jadeites. The raw stones are classified into following categories: jadeite of green veins, jadeite of good ground (i. e. icy and glassy ground, fine grain ground, coarse grain ground, and ceramic ground), jadeite of fancy colour and multi-colour, blackish green jadeite (the main mineral being the omphacite), and dry green jadeite (the main mineral being kosmochlor). This kind of classification can be regarded as an essential guideline and it is of great importance for the price evaluation and bidding of jadeite. Firstly, the jadeite can be described in the light of six components: skin, ground and colour of the ground,“Zhong”(referring to maturity degree, hardness degree, and compact degree between grains of the jadeite),transparency,colour, as well as crack and flaw. Secondly, the characteristics of the jadeite according to the classification of raw jadeite table are compared and then the exact type of the jadeite is found out. Thirdly, kinds of final jadeite products can be estimated and calculated, for example bracelet, pendant, ring and etc, which is the most suitable for the exact type of the jadeite. Fourthly, we estimate the value of raw jadeite through the price of the final jadeite products. Last but not the least, we adjust the price according to the prices of previous bid auction. The final estimated price could be used in the bidding. In the paper the author emphasizes on the importance of normative description of raw jadeite according to the six evaluation components. With the help of the normative description, the skins and inner features of the different jadeites can be distinguished. Combing the traditional and new classification and methods of raw jadeite evaluation, we are able to make a precise estimation.