The main mineral components of granite include pyroxene, plagioclase, a little olivine, biotie and trace magnetite. It is precise in structure with black luster and through hundreds of millions years aging, it is of uniform texture, nice stableness, high intensity and rigidity, and can maintain a high precision under heavy weight. So granite is applicable to the works of industrial production and laboratory measurement.

The precision of the Jingda granite surface plates is in line with the standards of advanced countries.Tolerance of planeness: StandardJB/T7975-1999Grade 000 = 1 × ( 1+d/1000 ) μmGrade 00 = 2 × ( 1+d/1000 ) μmGrade 0 = 4 × ( 1+d/1000 ) μmGrade 1 = 8 × ( 1+d/1000 ) μm( "d" is the diagonal mm ) (The measuring temperature is normally 20±2°C )

Physical Properties: S.G: 2970-3070kgs/m3 Compressive strength: 245-254N/mm2Elastic modulus: 1.27-1.47N/mm2Lindar expansion coefficient: 4.61 × 10-6/°CWater absorptivity: <0.13%Shore scleroscope hardness: more than Hs70