Visitors view royal-court enamel ware during an exhibition of cultural relics from the Palace Museum held in Qingdao Art Museum in Qingdao, east China's Shandong Province, July 6, 2018. The exhibition was opened for free to the public Friday and will last to July 28. (Xinhua/Li Ziheng)

A visitor takes a photo of a royal-court enamel vessel during an exhibition of cultural relics from the Palace Museum held in Qingdao Art Museum in Qingdao, east China's Shandong Province, July 6, 2018. The exhibition was opened for free to the public Friday and will last to July 28. (Xinhua/Li Ziheng)

Photo taken on July 6, 2018 shows a royal-court enamel vessel at an exhibition of cultural relics from the Palace Museum held in Qingdao Art Museum in Qingdao, east China's Shandong Province. The exhibition was opened for free to the public Friday and will last to July 28. (Xinhua/Li Ziheng)

Visitors view a blue-and-white porcelain of imperial kiln during an exhibition of cultural relics from the Palace Museum held in Qingdao Art Museum in Qingdao, east China's Shandong Province, July 6, 2018. The exhibition was opened for free to the public Friday and will last to July 28. (Xinhua/Li Ziheng)