Introduction to Turtle Stone: Turtle Stone is an exquisite and clear Taihu stone. It is a relic of Yunzhuang, the villa of Zhang Yanghao, a Sanqu master of the Yuan Dynasty, in Beiyuan. He refused to take the exam. At that time, there were 10 beautiful stones in Yunzhuang, which were called "Ten Friends". After the Ming Dynasty, it was moved to the Huangting, Confucius Temple and Baotu Spring in Jinan City.