Burning treatment is to rapidly heat the stone surface with a high temperature flame (about 1800 degrees Celsius) produced by mixing propane gas and high-pressure air to produce a rough surface texture within a few millimeters of thickness on the surface.

　　The principle of using flame spraying to produce a rough surface is to use the difference in thermal expansion characteristics of minerals composed of stone.

　　Before the burnt surface treatment, the stone should be coarsely ground, and the burnt surface treatment can only be carried out after grinding. In addition, the moving route of the flamethrower will show the directionality on the surface of the stone during processing. Therefore, the direction of the processing should be marked on the back of the stone before processing, so that the directionality of the surface of the stone after the burning treatment is consistent.

　　The principle of treating the surface of stone with burnt surface is to crack the minerals such as quartz and feldspar that make up granite, causing the surface of the stone to be damaged. Therefore, it is required that the stone slab treated with burnt surface should have sufficient thickness.

　　The surface of the stone after the burned surface is polished with an air jet polishing wheel to grind the fine protrusions of the burned surface to increase the color density of the stone.