Jadeite

Jadeite is one of the two distinct minerals known as jade (the other being nephrite). A sodium-aluminum pyroxene, it is rarer, harder, and generally more valuable than nephrite. The finest translucent emerald-green material, colored by chromium, is known as 'imperial jade' and ranks among the most precious of all gemstones.

Jadeite occurs in a remarkable range of colors, including white, lavender, yellow, orange, brown, and black, with green being most prized. It is an interlocking aggregate of microscopic crystals, which gives it exceptional toughness despite only moderate hardness.

The most celebrated source is Myanmar (Burma), with significant deposits also in Guatemala, Russia, and Japan.

Jadeite forms under the high-pressure, relatively low-temperature conditions found in subduction zones, where oceanic crust is forced deep beneath another plate. It typically crystallizes from sodium-rich fluids reacting with rocks at these blueschist-facies conditions, often in association with serpentinite.

Because these conditions are geologically uncommon, jadeite deposits are scarce and concentrated along ancient and active convergent plate margins. Myanmar's Kachin State hosts the world's premier deposits, where jadeite occurs in boulders within serpentinite and as alluvial cobbles. Guatemala's Motagua Valley is another major source, exploited since pre-Columbian times.

Jadeite is hard (6.5-7), extremely tough, and shows a smooth, slightly granular or dimpled 'orange peel' texture on polished surfaces under magnification. Quality pieces are translucent with a vitreous to greasy luster, and colors often appear in mottled patches or veins.

It is heavy for its size (specific gravity around 3.3). Distinguish it from nephrite, which is slightly softer, has a more fibrous splintery structure, and a different surface texture. Serpentine 'new jade' is far softer and easily scratched. Many imitations exist, including dyed quartz, glass, and treated jadeite; a gemologist's spectroscope or refractive index test gives definitive confirmation.

Jadeite is one of the world's premier carving and jewelry gemstones. Imperial jade cabochons, bangles, and beads command extraordinary prices, especially in East Asian markets. It is also carved into pendants, figurines, and intricate ornaments.

In Chinese culture jade symbolizes purity, virtue, and good fortune, and has been treasured for thousands of years. The Olmec and Maya civilizations of Mesoamerica revered Guatemalan jadeite for ritual objects and royal regalia. Metaphysically it is associated with harmony, prosperity, and protection, though such beliefs are not scientifically established.