Although the rough stone is mostly found in Upper Burma, the land the Chinese call Yuthian (the jade country), China is the home of jadeite. It has always been regarded there of great importance for, apart from its use in jewelry and ornament, it had, for many centuries, its uses in ceremonial and religious rites, as well as in ordinary domestic and official life. Definite shapes and colors each had special significance, and very early examples dating back to before the Christian era are still in existence. Axe heads and knives made entirely from jadeite were also used in still earlier days during a period which dates back to at least 3000 B.C. Such early specimens show subtle graduations of color and surface quality, with a simple form devoid of decoration.

It was therefore not only the beauty of jade which attracted the Chinese; the imperishability of the stone was, and is, to them an outstanding quality since religious and civil ceremonies are all attended by the wearing of certain jade objects. In fact, as far back as the dynasty of Tcheon (1134 B.C.), a special keeper of jade was appointed by the Emperor. The use of the material showed that the early Chinese were undoubtedly great artists. Their skill in the working of this stone is still unsurpassed, even though European lapidaries have available all modern tools and machinery which the Eastern lapidaries never use.

It is quite certain that small quantities of rough jadeite were sent from Burma to China at irregular intervals throughout many centuries, but owing to continual warfare between the two peo­ples, the long and arduous journeys which must have been re­quired to bring the stone from the mountainous country to China, and the primitive methods employed, the trade must have been carried on with much difficulty.

The most expensive and rarest quality is the uniformly colored translucent green, which, when free from flaws, almost compares with the emerald for beauty. By the Chinese, who are experts in classifying jade, this green color is compared to the vivid green in a peacock's tail. All shades of green are found, however, from the apple green to the emerald green, from the greenish white to the almost white. The poorer qualities, resembling mutton fat in appearance, are of little value and attraction, and although the luster of all jades may be classed as greasy, the medium and poor qualities do not take such a high polish as the best jadeite. Un­equal color, black marks and patches, and white patches are all faults which detract from the value of a specimen.

There is not much demand for the "fancy colored" jades. Orange, red, and yellow are amongst the cheaper grades, the lighter greens with green spots or mottled markings, pea greens, and sage greens are all of a moderate value, while the grays and whites are uninteresting and worth very little. The mauves and violets, generally pale, are attractive and are moderately costly, but none approaches the deep, translucent green in beauty, rarity, and value. Fifty-six thousand dollars (£20,000) has been paid in the United States for a string of jade containing only 125 plain round beads. This necklace was 30 inches long and weighed 304 carats, the center bead being only half an inch in diameter. And this necklace had no carved work on it, nor was it of any antiquity. At an auction sale in London during November, 1935, an oval jade bowl of a fine, emerald green color, 7 1/2 inches long by 5 1/4 inches high, was sold for $3,360 (£1200). Jadeite, therefore, might well be regarded as "precious," for it possesses all the necessary qualities of rarity, beauty, and durability, apart from high com­mercial value.

This is the most popular of the opaque green stones, and the rarity of fine colored specimens makes it the most expensive of the opaque gem materials. Its pleasing color and hardness render it suitable for most articles of jewelry that are worn, and the differ­ent shades of green with which we usually associate jade harmonize well with a number of other colors.

As a gem stone, however, its finer appreciation is very limited in Western countries, and we have to turn to the East, and par­ticularly to China, in order to observe with what care and exacti­tude this stone is considered. For in China, no other stone is re­garded with so much reverence; it is of such importance that it is considered as being precious and ranking above all other stones, including the diamond. In the East, it is connected with ancient traditions and customs, and its use dates back to many centuries. In the West, it was little used until the last century, and its gen­eral popularity still varies with fashion.

Actually, the term "jade" includes two distinct types of stones, although they have some properties in common. These are jadeite, more commonly known as Chinese jade, and nephrite, which is more generally called New Zealand jade, Greenstone, or Maori Stone. Both types belong to the monoclinic system of crystalog-raphy and both are generally found in massive form, boulders, waterworn pebbles, and not as crystals. Each is characteristically green in color, although the shades of green are different. Jadeite is a pyroxene, and nephrite belongs to the amphibole or horn­blende group of minerals. They are different in chemical com­position and in many physical properties. Yet they are generally considered under the one heading of Jade.

Imitations of turquoise are common, and many of these origi­nate in the East, although the real stone is also often carved by the Chinese into small figures and ornaments. Colored glass and china of a pale blue color to imitate the real stone are often seen, but a superficial glance is generally sufficient to distinguish them. A more ingenious material which may deceive is the one made from clay into which markings have been introduced, and this looks much like turquoise matrix. A glassy or highly polished surface should always promote suspicion, since the natural stone will not take a good polish. Again, many so-called turquoises are really odontolite or variscite, two natural minerals which greatly resemble turquoise in appearance although not in other respects. Variscite is more extensively used in the cheaper forms of jewelry than is generally realized; its popularity is due to its cheapness and to its similarity to turquoise when it is suitably set and treated for color.

Variscite is a hydrated phosphate of aluminum, and in its natural state resembles greenish turquoise in color, but it is softer, (having a hardness of only 4) and also lighter, the specific gravity being 2.55 and sometimes lower. It is found in large masses in both Utah and Nevada. The Nevada mines are centered at Colum­bus, an all but deserted mining camp situated some 4,600 feet high in an almost desert region.

Hardness is only 6, and turquoise thus falls below quartz in wearing qualities. A file will scratch it fairly easily; it is compara­tively brittle, and its color is almost certainly affected if im­mersed in any liquid or even in water for any length of time. It will therefore be seen that turquoise needs to be handled and treated with much care and that, for a ring stone, it is really most unsuitable. Its comparatively low value, however, would make it easily replaceable, although the matching of stones is more difficult. It is surprising how many different shades of blue can be seen in a parcel of turquoises when one makes comparisons.

Turquoise is never found as natural crystals, but always in an amorphous or crypto-crystalline state. It occurs in igneous or sedimentary rocks, filling veins and cavities. If a section is ex­amined under the microscope, doubly refractive grains or fibers are sometimes seen. The material resembles chalcedony in this respect, and it may therefore be said to be crypto-crystalline. In 1912, Schaller showed that some turquoise found in Virginia was apparently of crystalline formation. The refractive index is generally given as 1.61 to 1.65, the specific gravity also varying from 2.60 to 2.82.

The luster is decidedly waxy, and it is difficult to obtain a good polish on a surface. If this is attempted, the heat developed during friction between the stone and the polishing lap is sufficient to affect the color; it may even cause a crack or breakage. Most of the highly polished turquoises which one sees have had their color restored by artificial means after polishing. Nearly all are cabochon cut and all shapes are seen. Much of the fashioning of this stone is done in the East, where its use in ornament is almost universal and good specimens are highly valued.

This fine blue stone, although opaque, has been rated by some as a precious stone but despite its undoubted attraction and its rarity iri fine pieces, it cannot really compare with the transparent blue stones, such as the blue sapphire. Its color, a deep sky blue at its best, is one that is ever popular, for a fine blue is not com­mon in gem stones.

The general run of turquoises is, however, inclined to be a greenish blue to an apple green in color, and naturally these are not so attractive as the deeper blues. Veins and marks, general intrusions of the parent rock, often spoil pieces which otherwise would be good, although some prefer such markings if they are not too prominent since they give character to the stone. The natural color of turquoise, which is probably due to its copper constituent remains constant in artificial light, a property which its many imitations do not possess.