The material of the cutting tooth of Diamond coring bit is diamond or carbonizes tungsten. It is sintered in the alloy steel body by special welding techniques. The product is used mainly in petroleum and geologic exploration drilling to core rock sample. Its crown model includes double-taper type, arc type and tooth type. The kinds have diamond inside inlay, diamond surface inlay, PDC and polycrystal diamond. According to different geologic drilling, there are different using ranges.