The front is Han Li "Ke Jiuchang"
The back is Xingkai "Han Xwen 'Ke Jiuchang' three characters genuine Han Li Ye Mansheng carved", a legacy of the Jin and Tang Dynasties (The second character cannot be determined. It is suspected to be the character "brick" or "stele". Personally, I prefer the character "brick")
Chen Mansheng, whose real name is Chen Hongshou (1768-1822), whose courtesy name is Zigong and Haoman. Born, Laoman, Manshou, Mangong, also known as Jiagu Pavilion Chang, Xuxi Yuyin, Zhongyu Xianke, Zhongyu Taoist, were born in Qiantang, Zhejiang (now Hangzhou), and lived during the Qianlong and Jiaqing years. As one of the "Eight Masters of Xiling", he is the author of "Zhongyuxianguan Copy", "Zhongyuxianguan Collection", "Zhongyuxianguan Seal Collection", "Sang Lianli Guan Collection", etc., and his stage name is obvious. He is good at ancient prose and carving, and is famous for his calligraphy and seal cutting. He is proficient in literature, calligraphy, painting, and seal cutting, and is extremely talented.