Photo taken on July 23, 2019 shows tri-colored glazed potteries at a workshop in Nanshishan Village of Mengjin County in Luoyang City, central China's Henan Province. Sancai, or tri-colored glazed pottery, is made of white clay and coated with a layer of glaze. The producing technique of Sancai, which prevailed in the Tang Dynasty (618-907 AD), was very complex and listed as one of China's National Intangible Heritages in 2008. (Xinhua/Li An)