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Identification of jadeite and collection

Identification of jadeite and collection

2016-02-17

The problem about how to jade A, B, C goods identification on the market, can be roughly divided into the following several points:
First, the color removal method: first use light (suggested by the porcelain jade identification of special full spectrum flashlight) in direct sunlight was measured, with the special filter observation measured jade is it right? Apparent discoloration (usually mostly red), or white place is it right? Into meat pink, but as long as it is changed color. Is stained (C goods) or into the glue class (B goods). And then the transmission on the bright flashlight, a green colored colored head tail, with shades of transition spots into strips, and C goods in the light transmission, green were distribution is thin like in the grain around or crack. Through the color elimination method is determined as C goods, and other methods to distinguish A or B goods.

Second, sonic resolution method: A, B goods identification of jadeite Bangle generally dominated by listening to the sound. In the absence of crack under the condition of a bracelet with a finger up, picked up another bracelet or other hard objects lightly percussion (must be lightly percussion, force a there is damage to the bracelet, two is the sound may be wrong), a crisp sound, long echo, a metallic sound; B goods voice dull, hoarse.

Third, to identify the emerald color, luster and structure: pure natural jade, only after proper surface polishing, carving, forming and the traditional mild pickling surface or surface pier wax treatment, the structure is not affected by corrosion and damage. Natural emerald green distribution uneven, deeply shallow, most obvious color shape, a few color particularly good gourmet green jade not see color and shape; jade luster strong vitreous luster and glass luster, and similar to the color of jade, is uniformly distributed, only Grossular and vesuvianite jade luster is strong. Jade: jadeite, nephrite structure observation, grape stone, Fu Shanshi, although has fiber weaving structure, but the jade is become crystal weaving structure, nephrite is cloud structure, surface grape stone and California jade for radial fiber weaving structure, other similar jade are granular structure; when the emerald internal coarse particles, the naked eye can be observed similar fly wings like the gleam of “Cui sex”, when jade internal structure is fine, by virtue of the identification for 10 – 30 times the magnifying glass and bright flashlight also can observe the jade, jade is not the other green features.

Fourth, the use of special portable refractive optical microscope to observe the surface characteristics of jadeite carefully: usually use portable refracted light microscope 50 times were observed through microscope, refraction euphotic zone phenomenon, can be seen: a surface smooth as a mirror, have very strong vitreous luster. Just some small trachoma, pit is also in the mineral grains connected by triangles or polygons strip appeared. The better of jade in the refractive light area more complete clean, because the structure of the better and more detailed and more closely, after polishing the surface is smooth, no pits and crack connection phenomenon (because of the special structure of jadeite, its surface sometimes wavy phenomenon, feel rough, texture is very strong, so in the refractive light area sometimes undulating phenomenon, while other jade in any case does not have this phenomenon). Jade B goods usually due to immersion corrosion by acid or other liquids, the shape and arrangement of its internal mineral crystal is damaged, serious become chaotic cloud, because with pickling time is different, the corrosion degree is also different, the fine degree so generated net cracks are also different, some cracks a small, and even some large cracks; usually B goods trachoma pits appear to pores form, its characteristic is, round, deep, black, margin obtusely erosion. In addition, B goods surface covered with a bending line not a, arranged in a crisscross pattern mesh, dendritic grooves, as the aging of asphalt pavements in general. A surface although also can see fine lines, but that is over the fine lines between particles. Some low-quality goods, due to poor polishing, there may be some grooves, but these grooves appear only in local is not easy to be polished, and the edge is not corroded.

Fifth, measurement of jade density: where less than 3.33 should pay attention to. The reason is very simple, although the density is defined in the 3.25-3.43, but relatively low density of jade is a cargo and its texture is also is not very good, and the possibility of jade density in more than 3.33 of the goods and low B. Because not all of the jade are suitable for B. Generally speaking, do B cargo jade is coarse texture loose, poor transparency, with brown and black spots like material of jade; in addition, look from color, suitable for B cargo jade must have green. But not all with green jade is worth to do, only those green is better, but the transparency is not high, and there are many impurities is worthwhile in the emerald. More important is, now most of the process B goods materials are eight three jade, jade and the relative density of eight three was lower than 3.33, between 3.25-3.31. This will give us the correct identification of a cargo, B goods provides a reference data.

Jade A, B, C cargo processing: because the jade in the natural state, the geological environment and so on, the formation of jade contain many impurities, will greatly affect the appearance of jade, so the commonly used some methods to carry out some processing, in order to make it become beautiful, beautiful. Processing method is: will the jade immersed in particular acid neutralization bleaching liquid, to remove iron impurities in jadeite jade and some stains, and then waxing polishing treatment, the market most of jade to this process, this method is called “optimization”. Optimization in the trade in jade and without any Treated Jadeite is called “a cargo”. Processing jade B goods: the first step is to be processed jade soak in alcohol, and heated to about 300 degrees; in the acid treatment process, structure of some more impurities, jade is destroyed, therefore, people inject polymer to consolidation; second, the colorless oily “optical filler” epoxy resin or special, and vacuum high-pressure injection of jade, this method is called “Emerald filling treatment”; third, jade to the immersion acid etc., its surface is likely to become rough, so that the brightness decreases, so often in the jade surface coated with a thin layer of wax or resin and other materials, and then by mechanical polishing, we usually say “B goods” was born. In order to make the white jade color, often dyed green, purple colors in them, such a method called “jade dyeing processing”, known as “C goods”.