What does Four Treasures of the Study mean?

The musical instruments in the traditional culture of Han nationality in China are pen, ink, paper and inkstone. The name of Four Treasures of the Study originated in the Southern and Northern Dynasties.

Historically, what "Four Treasures of the Study" refers to has changed frequently. "Four Treasures of the Study" in Southern Tang Dynasty refers to Zhuge Bi in Xuancheng, Li Tinggui Mo in Huizhou, Chengxin Tang Paper, and Weilong inkstone in Wuyuan (originally in Huizhou, Anhui Province, but now in Jiangxi Province).

Since the Song Dynasty, "Four Treasures of the Study" refers to Hubi (Huzhou, Zhejiang), Huimo (Huizhou, now Shexian County, Anhui), Xuan Paper (now Jingxian County, Anhui Province, the ancient Ningguo government, the paper was produced by the government in the name of governing Xuancheng), Yan Tao (now Zhuoni, Gansu Province), Duanyan (now Zhaoqing, Guangdong Province, formerly known as Duanzhou) and Zhou She. Xuancheng is the only "hometown of Four Treasures of the Study" in China, producing Xuan paper (Jingxian), Xuan pen (Jingxian/Jingdezhen), Hui ink (Jixi/Jingdezhen) and Xuan inkstone (Jingdezhen).