Duanyan is taken from the east side of the stream at the end of Michelle Mountain in Antelope Gorge. Its color is blue-gray, slightly purple-blue, and poets in the Tang Dynasty called it "purple stone". Stone patterns include jade, gold and silver thread, gold star point, pork liver jelly, fire, burnt leaf white and so on; There are eyes in the stone, which are blue, green, purple, blue, white, yellow and black halo. The stone is thin and dense, wet and strong.
It is said that the inkstone made of the end stone has the characteristics of "silent grinding, no water consumption, no ink loss", "one side of purple inkstone can be worth thousands of dollars", and most of them are tributes of past dynasties. The appreciation, use, collection and inscription of Duanyan by celebrities in past dynasties have continuously enriched the cultural connotation of Duanyan.
In 669, Wu Zetian presented the calligraphy and inkstone of "the combination of the sun and the moon and the five stars" to Emperor Renjie.
Since the Tang Dynasty, the records of Duan Yan are inexhaustible. The ancient inkstone, the "Jade Belt Born" inkstone in the Song Dynasty, the "Dragon Snake" inkstone in the Qing Dynasty and the "Chibi Yanshan" inkstone are all famous Duan inkstones.