With one thick grit size face for rough grinding and the other fine grit size for finishing, such an sharpening stone is normally made of the black silicon carbide or green silicon carbide or brown fused aluminum oxide or white fused aluminum oxide with vitrified bond. The combination sharpening stone has got the advantages of easy carrying quick sharpening, suitable hardness and long service tile and can be used for sharpening all kinds of manual cutting tools. we also produce all kinds of presicion sharpening stone,ceramic fiber polishing stone..etc...