I am selling a set of two vintage commemorative stamps from China, "Ancient Chinese Scientists (Third Series)." Symbol: J.58 Issue Date: November 20, 1980 Issuing Authority: Ministry of Posts and Telecommunications of the People's Republic of China Background of the Issue: Reflecting China's glorious history of ancient science and technology, as well as the outstanding achievements of ancient scientists, and to inspire modern people's confidence in catching up with and surpassing the world's advanced scientific standards, the Ministry of Posts and Telecommunications of the People's Republic of China began issuing the "Ancient Chinese Scientists" series of stamps on August 25, 1955. "Ancient Chinese Scientists (Second Series)" was issued on December 1, 1962. Furthermore, on November 20, 1980, "Ancient Chinese Scientists (Third Series)," designed based on the original artwork of Chinese painter Fan Zeng, was issued by the Ministry of Posts and Telecommunications of the People's Republic of China. The design name of Stamp 1 (left) is "Ming Dynasty Scientist Xu Guangqi." Xu Guangqi was a Chinese calendar mathematician, agronomist, and famous Christian at the end of the Ming Dynasty. His courtesy name was Zixian, his pseudonym was Xuanhu, and his baptismal name was Paulus. He was also a politician who worked in the central government during the turbulent late Ming Dynasty. The design name of Stamp 2 (right) is "Warring States Water Conservancy Engineer Li Bing." Li Bing was a water conservancy engineer and politician during the Warring States period of China. He is known as the governor of Shu around 250 BC and contributed to the construction of the Dujiangyan Irrigation System. The stamp designs show careful consideration in the arrangement of the face value in characters. The elegant and refined calligraphy is well-balanced even as a single stamp, and when four are placed side by side, they respond to each other and create a sense of unity. Furthermore, in a block of four, the top, bottom, left, and right sides correspond neatly, creating a stable and dignified composition, and giving a sense of overall harmonious beauty. In addition, the birth and death years are noted after each person's name. Both stamps in the image are used. I believe they are in good condition for vintage stamps. Please check the details in the images. No returns or exchanges. Shipping costs will be covered by me.