What is natural black granite?

Granite is a common type of felsic intrusive igneous rock which is granular and phaneritic in texture. Natural black granite is of high strength, extremely homogeneous with find pores as well as a stably tight structure.


Why natural black granite?

The above-mentioned characteristics help to make natural black granite one kind of initial raw material, which can perfectly serve our purposes. Natural black granite is of high mechanical strength. The crystal structure contributes to excellent grinding and lapping. Natural black granite, which occur in the nature, is liable for plenty of different influences like pressure and temperature. It can be refined into precision measurement tools and machine components.


The physical characteristics of natural black granite

Specific Gravity:         3.03 g/cm3

Shore Hardness:          > 70Hs-80Hs

Tensile strength:          211Kg/cm2

Compressive Strength:         245-254Mpa

Linear Expansion Coefficient: 4.61´10--6/°C

Elastic Modulus:                 30-50Gpa

Water Absorptive:           ≤0.13%