Opal stones, the national gemstone of Australia, are displayed during the Hong Kong Jewellery and Gem Fair in Hong Kong, south China, Sept 19, 2011. A total of 3454 exhibitors from 46 countries and regions attended the five-day fair, which opened here on Monday. [Photo /Xinhua]  

Gem crafts in shape of Dong Chong Xia Cao, which means "winter worm, summer grass", a traditional Chinese herbal medicine, are displayed during the Hong Kong Jewellery and Gem Fair in Hong Kong, south China, Sept 19, 2011. A total of 3454 exhibitors from 46 countries and regions attended the five-day fair, which opened here on Monday. [Photo /Xinhua]