An emerald necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

A gold necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

Gold jewels are exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

A necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

An emerald necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

An emerald necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

A gem necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

An emerald necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

An emerald necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

An emerald necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

A gem necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)

A gem necklace is exhibited during the 30th Hong Kong International Jewellery Show in Hong Kong, south China, March 8, 2013. The five-day show attracted more than 3,300 jewellery exhibitors from 49 countries and regions. (Xinhua/Chen Xiaowei)