1. Sword has developed from bodyguard weapon and status symbol to one of the important weapons in melee combat. According to the analysis, Jian Qin is made of copper-tin alloy, with copper accounting for 76.39%, tin accounting for 2 1.38% and other 13 trace elements, and the hardness after tempering is equivalent to that of medium carbon steel. The surface of the sword body is oxidized by chromium salt, and it is still bright and sharp as new after being buried underground for more than 2000 years.
2. The secret of Jing Ke stabbing Qin without drawing a sword is that it is 90cm long, which is a famous sword in ancient China. Qin Shihuang cast bronze from the north. It is clear that the seal script of Qin Dynasty was carved by Li Si, three feet six inches. In the thirty-seventh year of the emperor, it was cast in three years.
3. Qin Dingjian is the masterpiece of China's excellent sword culture during the Spring and Autumn Period and the Warring States Period, and the first imperial sword in China. Therefore, it has been praised as "the first sword in the world" by later generations, and has become a highly respected treasure since the Han Dynasty, making it a must for China.