Chinese painting stone, also known as Archaic stone painting; Commonly known as flower stone. Caohuashi is named because the pictures on the stone mostly show monochrome or multi-color caohuashi patterns. Some people also call it China Chinese Painting Stone because of its rich interest in Chinese painting. In fact, the design of flower-grass stone is not limited to flowers, it can form figures, flowers and birds, landscapes and many other landscapes, and its aesthetic characteristics are not limited to China's traditional Chinese painting. Flower-grass stone with the style of printmaking and oil painting is not uncommon, but the names of flower-grass stone and traditional Chinese painting stone are gradually called.

Caohuashi protolith is the bottom rock of Gufeng Formation of Lower Permian about 250 million years ago, belonging to Upper Paleozoic. The lithology of the horizon where the flower stone is produced is: the upper part is dark red siliceous limestone, which is gray, yellow gray, beige gray and light purple gray after weathering, and the lower part is dark blue gray calcareous siliceous rocks and siliceous limestone, which are mostly gray, yellow gray, grayish white and beige gray after weathering. This is the horizon with the most grass stones, and the bottom is thin siliceous rocks with limestone.

The pattern of flower stone is the result of mineral filling along joints, fissures and capillary holes, and under a certain degree of weathering, various mineral elements color, ferrous ions and ferric ions color brown, brownish yellow, brownish brown, individual brownish red, brownish red, tetravalent manganese ions color brownish black, black, etc., chlorite color is light green gray, and mineral elements color, which makes its pattern appear colorful. The source of mineral filling in joints is not only the minerals of original rocks, but also a layer of volcanic tuff covered by Indosinian movement, which makes this layer of rocks undergo hydrothermal metamorphism to a certain extent, and with the coloring of various minerals, rich patterns are formed. The "sun" and "moon" formed by these patterns are the result of the cross section of the stem of single coral or sea lily, and these patterns are only exposed after the weathering of rocks, which is different from that of rock layers.