China Hard Materials Parts's first business in 1947 was fabricating sapphire parts (i.e. phonograph needles). This work was all accomplished through a diamond grinding process, which is extremely accurate, though painstaking, and the only practical method to machine complex shapes using this crystal material. Once we established our expertise working with extremely hard, yet fragile materials we began accepting work fabricating other extremely hard technical ceramic materials such as alumina, zirconia, silicon carbide, among others, as well as glass that included quartz and fused silica. China Hard Materials Parts(R) does not machine metals or plastics simply because they are too soft to be machined effectively with our fine diamond wheels. Please visit our materials webpage for a list of materials we have worked on in the past with links to specific material properties.