“Jade” is an umbrella term used to describe two specific minerals, jadeite and nephrite. In 1863, the French chemist Augustine Damour identified the two types of jade, although the differences between jadeite and nephrite had been known to the Chinese since the mid-18th century. Jadeite is the more valuable, and also the rarer of the two, as well as being the harder of the two varieties of the gemstone. The finest jadeite is called Imperial jade. Jadeite is the jade most often used for jewelry today.
Nephrite is not as hard as jadeite, but its interlocking crystalline structure, ironically, makes it a little stronger, and nephrite is the variety of jade most often selected for carvings, figurines, and was even used for weapons (such as daggers and clubs) in ancient times.
•Where is jade found?
Jadeite is found in Myanmar (formerly Burma), Russia, Japan, Guatemala; and California in the United States. (The finest jadeite comes from Myanmar.) Nephrite is found in China, Siberia (dark green), Taiwan, New Zealand, Switzerland, Brazil, British Columbia, Australia (black), Poland, Germany, India, Canada, Zimbabwe (dark green), Mexico; and in Alaska, California, and Wyoming in the United States.
•Color
Jadeite occurs in a wide range of colors, including the complete range of greens (including speckled green), lavender, brown, honey-yellow, white, black, and grey. Nephrite is mostly green, with gray, black, or brown undertones. Nephrite also occurs in a completely gray or black variety, and also in a grayish-white form sometimes referred to as “mutton-fat” jade and especially favored for carving figurines.
•Shape
Both forms of jade are cut and polished into beads, cut into cabochons, and carved into cameos, intaglios, and figurines. Jade is occasionally cut into the faceted gemstone shapes such as round brilliant or marquise, although cabochon is the more popular and more traditional style for jade.
•Durability
Jadeite has a hardness of 7 on the Mohs Scale; nephrite, a 6 1/2, and both are extremely tough and excellent to work with. Both carve well, set well, and can handle the jeweler’s torch with little if any problems. Sometimes, extremely porous jadeite may be impregnated with jeweler’s wax to stabliize extremely fragile natural “tunnels” in the stones (a common in the industry) and the larger cabochons treated in this manner may occasionally exhibit some pitting under prongs, but this can be prevented by having the stones periodically checked by a professional and repositioning the stone if necessary. Overall, jade is a very durable stone that can be worn safely under almost all circumstances.
•Quality
The quality of both types of jade is determined by:
- the intensity and uniformity of a stone’s body color (dark green is considered the highest quality, followed by lavender, red, yellow, white, and black)
- the number of flaws, cracks, spots, and blotchy areas (the fewer, the better)
- its texture, polish and finish (a smooth surface with a fine “grain” and a brilliant luster are a higher quality than a coarse, rough surface and a dull finish)
- a semi-transparent or extremely translucent visual appearance (light should seem to “enter” the stone as compared to stopping flatly at the surface of a nonreflective stone).
•Legend and lore
How jade received its name is a fascinating story. When Spanish conquistadors invaded Mexico in the 16th century, they discovered that the natives were wearing jade to cure kidney problems, so the conquistadors called the beautiful stone piedra de ijada, which translates to “stone of the loins.” Interestingly, the ancient Romans also believed that jade was a cure for inflammation of the kidneys, known as “nephritis.” Thus, the Romans called jade by the Latin term lapis nephriticus, which eventually was shortened and Anglicized to nephrite. Jade’s range of “natural” colors has long been associated with the bounties of nature, and many believe that the stone is a gift from God.
Jade has various mystical and spiritual properties attributed to it, including inner purity, higher consciousness, intellectual superiority, the art of music, and the virtue of loyalty. It also represents good fortune and abounding health and many wear it as an emblem of these attributes. Jade is also reputed to stimulate optimism and promote understanding of the opposite sex. Also, white jade can purportedly cure intestinal trouble, while black jade is believed to imbue the wearer with strength.
•Care
Clean your jade jewelry in a mild soapy solution (don’t soak it more than a few minutes) and rinse it well under warm water. Avoid exposihg jade to excessive heat, as some forms of color-treated jade may fade; also avoid chemicals such as ammonia-based jewelry cleaner and harsh chemical cleaners.
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