The natural diamond (ND) cutting tools, widely used in the metalworking industry, are made through a special welding of natural diamond to a shank. It is suitable for applications that require excellent surface finish qualities, high heat resistance, and for applications when electrical conductive materials are an issue.  Two types of ND cutting tools, namely the sealed cutting tools and the brazed cutting tools.  The sealed cutting tools are mainly used for processing a mirror face of clock and decorative products while the brazed cutting tools are tuned for turning, milling and grinding that requires high precision, high vibration resistance capability, and mirror-face of surface finish.