Tru Stone - Starrett

Tru Stone - Starrett

Tru-Stone Technologies, marketed under the Starrett brand, is a manufacturer of precision granite surface plates and metrology reference tools. The L.S. Starrett Company, founded in 1880 in Athol, Massachusetts, is one of the most respected names in precision measurement, and its Tru-Stone product line represents the granite surface plate segment of its metrology portfolio. Granite surface plates serve as primary reference datum planes in dimensional measurement, offering superior flatness, rigidity, and vibration damping compared to cast iron alternatives.

Tru-Stone granite plates are manufactured from select black granite and finished to Grade A, Grade B, or Laboratory Grade tolerances as specified by federal standard GGG-P-463. They are available in a wide range of sizes to support layout, inspection, and assembly operations.

Key Product Lines

• Granite Surface Plates — Grade A, Grade B, and Laboratory Grade precision reference planes for dimensional measurement and part layout
• Surface Plate Stands & Accessories — mounting stands and workstation accessories for surface plate setup

Industries Served

Tru Stone - Starrett granite surface plates are essential in quality control departments, metrology laboratories, calibration facilities, tool rooms, aerospace component inspection, precision machining shops, and automotive manufacturing. They provide the stable, accurate reference surface required for coordinate measuring, height gauging, and part layout operations.