Yan Tao was famous all over the country in Song Dynasty, and it has been mined for more than 900 years. According to legend, in the early Song Dynasty, some people quarried stones at the bottom of Taohe River near Lintan and Lintao to make inkstones. Later, due to the flooding of Taohe River and the diversion of the river, the quarrying place could not be found. Zhao Xihu in the Southern Song Dynasty wrote in Gu Yan Bian: "Apart from the last two stones, the bluestone north of Taohe River is the most valuable. Green as blue, moist as jade, ink does not reduce the tail rock of the stream. But the stone is at the bottom of the Lintao River, which is not made by human beings and is of great value. Although it has been handed down from old times, I have never seen it.

There are several kinds of Yan Taoshi, one is duck's head green, also known as "green stone", which is green in color, wavy in grain, hard and fine in nature, like jade, and is superior to Shi Tao. If the green lines are mixed with yellow marks, it is even more precious. Second, parrot green, dark green, delicate stone, with dark "ink spots" eye-catching. The third is Liu Qing, with vermilion spots in the green and hard stone. Fourthly, light green pottery stone has the characteristics of slow water seepage. Yan Tao, known as "Taohe Stone inkstone" or "Taohe Green Stone", is one of the four famous inkstones in China. Because the inkstone material was produced in Taohe River, and the source of Taohe River was in ancient Zhou Tao, it was named Taohe inkstone or Yan Tao for short. Yan Tao made of Taohe stone has the advantages of fast ink development, fine ink grinding and no damage to the pen. The preciousness of Yan Tao's inkstone platform lies not only in its excellent stone quality and bright color, but also in its diverse shapes and fine carving. Yan Tao's inkstone style is dignified and heavy, simple and elegant, which is different from other inkstones in terms of technology. Filling lines with appropriate thickness with black is a major feature that distinguishes Yan Tao from other inkstones.

Yan Tao is named after Taohe River, the main tributary of the Yellow River in northwest China. Its inkstones are mainly produced on cliffs such as 1 Cliff, Shuiquan Cliff, Naer, Kari Mountain and Zhagan Cliff in Zhuoni Yantao Township, Gannan Tibetan Autonomous Prefecture. Because Zhuoni was under the jurisdiction of Zhou Tao in ancient times, it was named Taohe Green inkstone. Taohe stone belongs to Devonian fine mud shale, which was metamorphic by water rock. It is elegant in color, fine in structure and contains a variety of metal particles. This stone is as delicate as jade. When it is knocked silently, water droplets will be produced immediately. Used for inkstone making, it is water-saving, cold, non-freezing, non-slippery, ink repellent, and moderate in hardness. It has the advantages of fast ink development, fine grinding, no damage to the pen and free writing. The color of Yan Taoshi is mainly turquoise, especially "yellow label and green wave", and the production process is complicated. The main processes include quarrying, material selection, cutting, design, blank making, mold opening, sealing, carving, polishing and box matching. Yan Tao carving technology can be divided into two ways. East Road School is dominated by carving dragons, mainly in Baozi, Weixin and other places in Min County. The West Road School is mainly composed of carved birds, which are distributed in Min County and its surrounding areas. Minxian steamed stuffed bun and prestige craftsmen are famous for combining the skills of the two factions in one furnace. Yan Tao carving technology also permeates the circular carving technology of jade carving and tooth carving, the relief technology of brick carving and stone carving, and the seal cutting technology of wood carving and stone carving. Feng Fei, Youlong, is superior to Duanyan and She Yan in production technology, and has the reputation of "Zhou Tao is like a stone, Duanzhou is like this".

Since ancient times, Yan Tao's craftsmanship has been under the jurisdiction of the feudal Tusi yamen, and it has been kept strictly confidential, from sons to friends, from men to women. Since the Ming and Qing dynasties, the demand has increased greatly, and the number of carving technicians has increased and their skills have improved. In recent years, dozens of outstanding carving experts such as Li, Li, Cai, Zhang Yan and so on have emerged, and their skills are getting better and better. Craftsmen are all over Min County, Zhuoni, Lintan and other places. Yan Tao is a business card of Dingxi culture. 1997 When Hong Kong returned to the motherland, Yan Tao Factory in Minxian made an inkstone specially for Gansu Provincial People's Government as a gift to the Government of the Hong Kong Special Administrative Region as a permanent memorial. 1999, 99 dragons were carved on an inkstone, symbolizing the gathering of dragons and the return of all ethnic groups, and creating a new era of carving skills in Yan Tao.