Jade tops the list of touchable, wearable gems. Something about jade makes many people want to hold it or rub their thumbs across it. And whoever gave jade its descriptive names—like melon, apple, and spinach—must have thought it looked good enough to eat.
The term jade refers to either of two rocks, jadeite and nephrite, which look alike but are chemically different. Nephrite, a calcium magnesium silicate, is the “original” jade. Jadeite, a sodium aluminum silicate, is the rarer and more valuable of the two jades and is the subject of this article.
History and romance. Nephrite jade was discovered in what is now far western China (formerly Turkistan) nearly 5,000 years ago and has long been associated with Asian culture. It’s said that the wearer of jade imparts an aura to the gem, giving it greater life. But the jade mystique has been all but hidden to the West.
Jadeite jade was discovered in Burma (now Myanmar) in the middle of the 18th century. The intense, emerald-like semitransparent green vitreous variety, termed “imperial jadeite,” elevated the jade family to an even higher status in the Far East.
Jadeite’s mystery derives in part from its remote origin. The finest-quality jadeite in the world comes from Kachin State, in and around the small town of Hpakan. This jadeite-producing region is located in northern Myanmar in what’s called the “jade tract” or “jade land,” which encompasses approximately 400 square miles. Until 1996, no “westerner” had set foot in the region since Dr. Edward Gübelin visited in 1963.
Lovers of jadeite know there’s more to the gem than its color. Its smooth, cool feel and the clear, high-pitched tones that result when it’s gently tapped are also part of jadeite’s sensuous nature.
Color variations. Jadeite occurs naturally in a variety of colors, including green, mottled green and white, brown, brownish-orange, yellow, and lavender. The most popular colors are green, lavender (or mauve), white, and what’s called “red”—actually a golden reddish-brownish-orange that’s more carnelian-colored than red.
Jadeite also can be colorless and semitransparent. Such varieties are known as water, ice, or crystal jade. More translucent specimens are called white jade or “pure” jade. Water jade hasn’t had much of a following in the past, but a recent surge of interest in the colorless semitransparent material may put prices on a par with those of colored jadeite.
Qualities. Jade quality is determined by transparency and by evenness and intensity of color. As transparency increases from opaque through translucent to the more rare semitransparent and transparent, the value of the gem rises. Ice jade can display transparency with an almost moonstone-like reflection. Since 1998, Christie’s Hong Kong auction house has seen some outstanding ice jade come up for sale, confirming its rise in popularity.
Another important quality of Burmese jadeite is its exceptional durability. Jadeite jade has a very compact interlocking crypto-crystalline structure, resulting in a stone that can be polished into bracelets and rings. Nephrite jade is actually more durable; it has an interlocking fibrous structure that allows it to be fashioned into hammers and axes and still not break.
Besides Burmese jadeite, which is considered the most desirable and expensive, commercial deposits have been reported in Guatemala and Russia. Small deposits of jadeite exist in Mexico, California, Japan, and the Swiss Alps.
Pricing. Prices for top-quality “Imperial” jadeite range from about $6,250 for an 8x10 mm cabochon to $50,000 for a 13x18 mm cab. The common apple-green jadeite is more affordable at $375 for an 8x10 mm cabochon and up to $3,000 for a 13x18 mm cab.
Ice jade cabochons are now priced at $200 to $300 each for smaller cabs. Top-quality specimens reaching sizes of 13x18 mm can cost close to $1,000 per cabochon.
Black jadeite is gaining in popularity. (Most black jade is nephrite.) Although black jadeite from Burma is not as uniform as the best black nephrite, a few new mines in Guatemala are yielding a beautiful, compact black jadeite that is the finest black jade on the market. Prices are much higher than those for the best black nephrite. A strand of fine 12-mm black jadeite beads recently sold for close to $10,000.
Enhancements. “B” jade is the term applied to acid-soaked, bleached, polymer-impregnated jadeite. Since people looking for jadeite are increasingly aware of the treatment, most fine stores in Hong Kong provide certificates claiming “no polymer impregnation.” Assume that all jadeite has been treated with polymers unless specifically stated otherwise.
Care and cleaning. Don’t steam jadeite! Most jades are waxed, and steam will remove the wax. Steaming can also blast out surface-reaching inclusions. Use mild soap and warm water. If you’ve already steamed a piece and you notice the luster is diminished, you can wax it yourself. Beeswax and candle wax work well.
Bench settings and precautions. Jadeite is a tough stone, but like most gems, it cannot be molded into shape. Many jadeite rings are set with jade “saddles,” so named because of their shape. Many gems have been broken as a result of sizing saddle-set rings, from trying to bend the jadeite to a smaller size or trying to stretch it to a larger size. Jadeite can take heat, to a point—beyond about 600º C, it turns brown.
When working with black jade, take precautions to protect the polish, which will show every nick and scratch. “B” jade isn’t affected by heat and light, but acetone, which is used to remove setting glue, will break down the polymers used to enhance it. When setting “B” jade in platinum, be careful not to push the prong too hard against the gem—it can be pushed into the stone.
Recommended reading. For more information about jade, see the following:
Jade by Fred Ward (Gem Book Publishing, 1996).
“Burmese Jade: The Inscrutable Gem” by R. Hughes, O. Galibert, G. Bosshart, F. Ward, T. Oo, M. Smith, T.T. Sun, and G. Harlow, Gems & Gemology, Spring 2000.