China will hold its fourth annual international mineral and gem exhibition in Hunan province's Chenzhou city from May 19 to 23. [Photo provided to China Daily]

The expo, officially known as the China (Hunan) Mineral and Gem Show, is the largest of its kind in Asia. Jointly organized by the Hunan government and the Ministry of Land and Resources, it plans to offer 2,300 booths of international standard in four major halls with a total space of 130,000 square meters this year, according to Yi Pengfei, the Party chief of Chenzhou.

Speaking at a news conference on Friday in Beijing's Great Hall of the People, Yi said the expo aims to boost his city’s annual gem sales to 30 billion yuan ($4.76 billion) by 2020.

Chenzhou is known for its rich mineral resources.

Last year more than 380,000 people came to the expo and purchased about 1.6 billion yuan worth of gemstones from sellers from 85 countries.

Starting this year, the organizers will launch an online sales platform for international mineral and gem trade, in line with the nation's Internet Plus strategy, according to Zhang Xihui, Chenzhou's head of publicity.

Meanwhile, Collector's Edge Minerals Inc, based in Golden, Colorado, in the United States, will display the world's largest float copper specimen, which weighs approximately 26.6 tons, at the expo.

Separately, Chenzhou plans to announce at the expo that Tucson in the US and Kimberley in South Africa, both known for their stone industries, have been Chenzhou's sister cities, says Yi.

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