Varieties of Jade Gemstones
Jade has been cherished for over 7,000 years. In ancient times, its remarkable toughness made it an ideal material for crafting weapons and tools across various regions. For more than 2,000 years, jade played a significant role in Chinese religious practices, with mythical figures and symbols meticulously carved from it. In pre-Columbian Central America, jade was held in higher esteem than gold. Browse through our collection of jadeite gems for sale.
Only in 1863 was it discovered that jade is actually not a single mineral but that there were different types of jade. What was traditionally called jade is in fact two separate and distinct minerals; jadeite and nephrite.
Nephrite is the more common form of jade. Nephrite ranges in color from mid- to dark-green or grey-green, but it can also be white, yellowish or reddish. Nephrite is slightly softer than jadeiter; nephrite has a hardness of 6 to 6.5 on the Mohs scale, while jadeite scores 6.5 to 7. They have quite different chemical compositions as well; nephrite is calcium magnesium iron silicate while jadeite is sodium aluminum silicate. The two minerals also have different densities. Jadeite has a density of 3.30 to 3.38 while nephrite is less dense at 2.90 to 3.03.
The two types of jade crystals even have different crystal structures. While jadeite's structure is an arrangement of grainy crystals, nephrite is made up of fibrous crystals that interlock in a matted texture. These densely packed and interwoven fibers are extremely resistant to fracturing. So while jadeite is the denser and harder jade, nephrite is actually the tougher of the two.
All of the traditional Chinese jade is nephrite, since there are large deposits of nephrite in China, but no jadeite. Jadeite first came to China from Burma in the 18th century. Before the introduction of jadeite, the Chinese tended to value translucent white nephrite, known as 'mutton fat' jade. The jadeite from Burma came in a wider range of colors, including green, lavender, yellow, black and white. The rarest and most valuable jadeite is imperial jade, which is colored by traces of chromium. It has color and transparency rivaling fine emerald, though imperial jade is slightly more yellow in tone. In fact the revered Emerald Buddha in Wat Phra Keow in Bangkok is believed to be composed of fine jadeite, not emerald.
Jadeite deposits are principally found in Upper Burma. Other deposits are found in Japan, Canada, Guatemala, Kazakhstan, Russia and California. Nephrite deposits are found in China, Burma, New Zealand, Australia, Brazil, Canada, Zimbabwe, Russia, Taiwan and Alaska.
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