Variety of jadeite pyroxene used as a gem or ornamental material consists of microcrystalline aggregates which, together with similar aggregates of tremolite-actinolite amphibole (nephrite), come under the general name of jade. For reasons of clarity, we shall therefore be using the term jadeite jade, rather than either jadeite or jade alone.



Appearance:
Jadeite jade is semi opaque to highly translucent aggregate of juxtaposed, very firmly interconnected granular crystals. Only in rare instances are their visible elongated crystals in fiber radiating or parallel groups. General impression is not so much of individual crystals as of a mass with fairly finely interwoven network of numerous minutes discontinued. These are the boundaries between one crystal and another of the cleavage surfaces inside some of the crystals. Despite this minutely fractured appearance, the principle characteristic of jadeite jade, infact, extreme intensity and toughness. On the surfaces of the antique pieces in particular, one can see a similar network of small discontinuities which keep the pieces from having a perfect polish. On modern pieces polished with diamond powder. This network is much less visible. Many different shades are possible, the most valuable being emerald green. Jadeite jade of this color is quite translucent and is called imperial jade. Other shades of light and bright green are also very lively and attractive. Dark is less common. The most frequent color is semi transparent to nearly opaque white, or of-white to very pale hazel; other are red(generally of orange or brown few), yellow, light and often grayish blue, grey, pink, and pale lilac. The brightest color generally occurs only in zones or in blurred, fringed streaks within the block. Pebbles recovered from alluvium of ten have an outer layer of a brown color because of oxidation that fades away on the inside. It is used as a gem, cut en cabochons or engraved stones for settings, beads, or other ornaments, especially when the background or limited patches of color are attractive shades. Last but by no means least, jadeite jade, like nephrite jade is made into exclusive types of decorative where or small sculptures. Because of its tenacity, which is almost equal to that of metals, generations of craftsmen in the far east have used it to produce staggering tours de force, such as chains with enjoined, individual links made from single pieces of stone, thin-walled vases generally with loose links on the handles and lids, cutting weapons, cups with engraved decorations, buckles, and other finely pierced objects. Its other distinctive feature, the presence of patches and streaks of bright color on inside and outside the uncut stones, has been manipulated with wonderful multicolored pieces.



Distinctive features:
Its almost alabastine translucence, the minute internal network of discontinuities and corresponding effect on the outer surface, its degree of hardness, the graduated streaks of color, and incomparable shades of green, are frequently sufficient to distinguish jadeite jade from similar material of lesser value, notably serpentine(which is highly translucent, greenish white to oil green, of uniform color, less hard, and less dense) and what is known as Transvaal or Pakistan jade(which is a mixture of microcrystalline hydrogrossular and vesuvianite, that ranges from highly translucent to almost opaque, lacks the internal appearance of jadeite jade, and has a rather different range of colors, fractionally higher density, and higher indices). But many natural materials are occasionally used as substitutes, and may be hard to tell them apart.



Occurrence:
Most jadeite jade used in Chinese art since the latter half of the eighteenth century and most of that used today come from northern Burma. Thus, nowadays, the name “Burmese jade” is synonymous with jadeite jade. It has also been found in Japan, the United States (California), and Guatemala, and only rarely in a few other places. It is, therefore, much less common and more localized than nephrite jade.



Value:
Jadeite jade has very wide range of possible value. As a gem, the translucent emerald green variety known as imperial jade can fetch prices only just below those of the principle gemstones, particularly emerald, which it so much resemble. Yet pieces in other color are worth no more than fine, hard opaque stones. Where the material is used for carving and engraving, the value depend very much on the quality of the workmanship, the skill with which any patches of color have been exploited, and the standard of finish. It is, nevertheless, the most valuable material used for this purpose, worth more than nephrite jade, except for very finely work or antique pieces, where no distinction is made between the two.



Simulants and Synthetics:
Some whitish pale-green or green aventurine, also of granular structure, is occasionally used as a substitute for jadeite jade and known as Indian jade, though it lacks the exceptional mechanical and chromatic properties of true jade. Synthetic jadeite does not exist. A problem which has arisen recently over jadeite is that of coloration. Because of the minutes discontinued present in the mass, it is easily impregnated with artificial dyes, to pleasing effect. In this way, for example, whitish jadeite can be made to look like the much more highly priced imperial jade; and the other colors are also often imitated in this way. One can usually distinguish cases in which the color rather than being contain in individual crystals is distributed in the minute fractures and cleavages of the mass, but a microscope is needed for this.