Stone mill grinding wheat that kind of stone is good

With sandstone or wheat stone grinding good. These 2 kinds of stone wear resistance is better, fine texture, wear-resistant, and does not fall slag, no radiation, but also on the life of the body health what is favorable. Stone mill is generally used to grind wheat, corn, soybeans into flour a milling tool, usually has the upper and lower two discs rotating back and forth, along the texture of the outward movement, in the rolling over the two levels when it is crushed, forming powder.