HARD bargaining is the name of the game among the dozens of jade wholesalers who line a four-block stretch of Canton Road between Jordan and Yau Ma Tei. Shopkeepers use their wits and knowledge of the market to get the best prices and move 80 per cent of the jadeite sold in Hong Kong - the world's premier jade trading centre. Many traders forgo a shop altogether and sell their wares from their pockets on the streets. To prevent their prices from being overheard, buyer and seller often practice finger bargaining, a complex set of finger and hand grips done under the cover of a newspaper or towel. So what is the novice, surrounded by such goings-on and overwhelmed by the variety of jade available, to do? How to avoid having a low-quality trinket palmed off as something valuable? There are two types of jade: nephrite and jadeite, which is more valuable. Jadeite quality is judged by colour and translucency. The colour should be even, without black spots or brownish iron stains. Avoid white clouds too, if possible. 'Beginners tend to buy apple-green pieces, but collectors want emerald-green,' said Eddie Fan, manager at Chui Wah Jewellery in Jordan. The more translucent the stone the better, because translucency is an indication of fine texture. 'It should feel smooth to the touch, not fibrous,' said Rose Wong, a jadeite jewellery specialist at Christie's. As with most gemstones and jewellery, jadeite is not a short-term investment. It should be held for a number of years before any profit can be realised. During the 1980s, the value of jadeite surged by 10 per cent to 20 per cent each year. But prices have fallen since 1990. 'It is now holding its value and prices should start to go back up in the next one or two years,' Mr Fan said. Buying jadeite can be hazardous for the novice. Many gemstones that are not jadeite, including quartzes and even dyed glass, are passed off as the real thing. Beware of such misnomers as 'Australian jade' or 'new jade'; these are different stones. There is also the widespread problem of bleaching, a treatment that improves the stone's colour but damages its internal structure, making it friable. The smell of bleach can sometimes be detected along Canton Road, where several businesses specialise in the process. Within the trade, jadeite is classified into types A, B and C. A-type jadeite is natural and untreated; B-type is bleached and resin-impregnated; and C-type is dyed. It is estimated that a third to half the jadeite on the market is bleached and an increasing amount is dyed. The best advice is to go to reputable shops, such as those carrying the Hong Kong Tourist Association's logo. Get recommendations from people who are knowledgeable in the trade and attend jewellery exhibitions and auctions to get a feel for quality and prices. When you buy, get a receipt that spells out exactly what you are getting, says Chan Wing-kai, chief complaint and advice officer at the Consumer Council. 'If you are buying A-type jadeite, the receipt should say 'A-type, natural colour, no artificial treatment and no bleaching or dyeing',' he said. When buying A-type jadeite costing more than $10,000, it is wise to ask for a laboratory certificate that says the stone is untreated. 'Ideally, the certificate should be signed by two qualified gemmologists. Their names should be printed clearly and their qualifications listed,' said Dominic Mok, chief gemmologist at the Asian Gemmological Institute and Laboratory. If the shop does not provide a certificate or if you want to have your jadeite tested independently, a number of laboratories in Hong Kong provide this service. Fees range from several hundred dollars to several thousand, depending on the stone's value.