Description
A very hard stone ranging in color from pale to dark green that is commonly called jade. Jadeite is composed a sodium aluminum silicate that usually contains small amounts of iron, calcium, and magnesium. The tough stone is hard enough to scratch glass. Though less common than nephrite (the other jade mineral), jadeite is highly valued for its translucent glassy appearance. Jadeite is primarily found in Japan (Omi, Kataki), China, Myanmar (formerly Burma), New Guinea, the Ural Mountains, Mexico (Celebes), Guatemala, and the U.S. (California). It has been gathered or mined since Paleolithic times. Jade was used for small utensils, carvings, beads, bracelets, and cabochon jewelry. Emerald green color jadeite was highly valued and known as Imperial jade. The grass green variety of jade obtained from near Tawmaw in Myanmar is called Ayah kyauk. Other colors include purple, blue, gray, black, white, red, pink, and orange. When heated to 1000 C, jadeite becomes glassy and may melt. Since the 1980s, some of the finished commercial jadeite (C-jade) stones have been impregnated with resins to improve their transparency.
Synonyms and Related Terms
jade; Imperial jade; Ayah kyauk; Jadeit (Deut.);jadéïte (Fr.); jadeiet (Ned.); jadeíte( Port.)
| Na(Al,Fe)Si12O6 |
| 6.0-7.0 |
| 3.33-3.34 |
| 1.64-1.69 |
Other Properties
Monoclinic system with fibrous or granular crystalline masses.
Luster = vitreous to waxy. Streak = white
Cleavage is good in two directions (87 and 93 degrees)
Fluorescence: may have pale white color in long UV light.
Max abs = doublet at 691.5 nm with pyroxene band at 437 nm and others at 655, 630 nm
Additional Information
° E.West Fitzhugh, "Jade" The Dictionary of Art, Grove's Dictionaries Inc., New York, 1996.
° Mineralogy Database: Jadeite
° Michael O'Donoghue and Louise Joyner, Identification of Gemstones, Butterworth-Heinemann, Oxford, 2003
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Last updated on: 7/7/2009 10:52:22 AM
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