Natural granite seasoned for thousands of years is free from deterioration or dimensional change over time.
Granite surface plate has many advantages over cast iron surface plates: Twice as hard as cast iron. Minimal changes in dimension due to temperature changes. Free from wringing, so there is no interruption of work. Free from burrs or protrusions because of the fine grain structure and insignificant stickiness; this ensures a high degree of flatness over a long service life and causes no damage to other parts or instruments.
Trouble-free operation for use with magnetic materials. Long life and rust-free, resulting in low maintenance costs.
Mitutoyo granite surface plates meet or exceed federal specification GGG-P- 463c. Each surface plate is shipped with a Certificate of Accuracy which guarantees its accuracy and verifies its traceability to NIST.