A worker makes an earthenware jar at Bitan Earthware Plant in Longchang County, southwest China's Sichuan Province, Dec. 23, 2015. Longchang County has a history of more than 600 years in making earthenwares with its tombarthite-rich earthenware slime. Its annual production value from the earthenware industry is estimated to exceed one billion yuan (154.4 million US dollars). (Xinhua/Jiang Hongjing)

A worker makes earthenware jar at Bitan Earthware Plant in Longchang County, southwest China's Sichuan Province, Dec. 23, 2015. Longchang County has a history of more than 600 years in making earthenwares with its tombarthite-rich earthenware slime. Its annual production value from the earthenware industry is estimated to exceed one billion yuan (154.4 million US dollars). (Xinhua/Jiang Hongjing)

A worker toasts bases of earthenwares at Bitan Earthware Plant in Longchang County, southwest China's Sichuan Province, Dec. 23, 2015. Longchang County has a history of more than 600 years in making earthenwares with its tombarthite-rich earthenware slime. Its annual production value from the earthenware industry is estimated to exceed one billion yuan (154.4 million US dollars). (Xinhua/Jiang Hongjing) 

Earthenware jars are seen at Bitan Earthernware Plant in Longchang County, southwest China's Sichuan Province, Dec. 23, 2015. Longchang County has a history of more than 600 years in making earthenwares with its tombarthite-rich earthenware slime. Its annual production value from the earthenware industry is estimated to exceed one billion yuan (154.4 million US dollars). (Xinhua/Jiang Hongjing)

Earthenware jars are seen at Bitan Earthernware Plant in Longchang County, southwest China's Sichuan Province, Dec. 23, 2015. Longchang County has a history of more than 600 years in making earthenwares with its tombarthite-rich earthenware slime. Its annual production value from the earthenware industry is estimated to exceed one billion yuan (154.4 million US dollars). (Xinhua/Jiang Hongjing)

A worker examines quality of earthenware jars at Bitan Earthware Plant in Longchang County, southwest China's Sichuan Province, Dec. 23, 2015. Longchang County has a history of more than 600 years in making earthenwares with its tombarthite-rich earthenware slime. Its annual production value from the earthenware industry is estimated to exceed one billion yuan (154.4 million US dollars). (Xinhua/Jiang Hongjing)

A worker examines quality of earthenware jars at Bitan Earthware Plant in Longchang County, southwest China's Sichuan Province, Dec. 23, 2015. Longchang County has a history of more than 600 years in making earthenwares with its tombarthite-rich earthenware slime. Its annual production value from the earthenware industry is estimated to exceed one billion yuan (154.4 million US dollars). (Xinhua/Jiang Hongjing)