Types: There are two types of jade - jadeite and nephrite. Nephrite is used mainly in carvings and big antique pieces. Jadeite, which is rarer and more expensive, is often used in jewellery.
Price: The price of a stone is difficult to define given the large variations in colours and materials. Learn more about pricing by visiting auction houses, shops and exhibitions. A piece of jadeite may cost about 400 times more than nephrite.
Reliability: Visit reputable shops where jade pieces come with certificates from internationally recognised laboratories, such as the Gemological Institute of America and Hong Kong Jade and Stone Association.
Colour: Jadeite comes in a wide variety of greens. Some like it in lighter tones. The lighter tone is highly desirable to people in Hong Kong. In Taiwan, they prefer dark green.
Brilliance: The more brilliant the colour the more valuable. Bright apple green, shocking pink and milky white colours are worth more than spinach green, dull pink or beige.
Translucency: The more translucent the jade the more valuable. Jade becomes more translucent the thinner it is cut.
Thickness: The thicker the jade the more valuable. However the trade off is the translucency. The thicker the jade is, the less translucency. When the thickness is doubled, the price could be four or five times higher. Thick and translucent jade is rare.
Comparison stone: Shop with a comparison jade - something small but beautiful which will not cost a lot (below HK$1,000). It will help you to compare the qualities of the stones by placing them next to each other.
Mirror: Most jadeite in jewellery is mounted on a reflective surface, like a mirror, to improve the translucency. Note that a good piece of jadeite must be translucent without any backing. A piece that is not backed is more expensive.
Treatment: Some jade in markets is either bleached or dyed to produce the desirable shades of green. Bleached stone will last for three to 10 years. Dyed stones might last for six months.