Black granite is an igneous rock that is highly valued for its physical properties, making it a popular choice for precision machine components. Government tests have shown that fine-grained black granites possess superior strength, density, and lower absorptivity than other granites. These qualities make black granite an ideal material for precision machine bases, air-bearing surfaces, and accessories.

One of the primary advantages of using black granite for precision machine components is its high modulus of elasticity. Since black granites contain no crystalline quartz and little mica, they are less likely to fracture under heavy loads, producing superior load-carrying capacity. This property makes black granite a popular choice for applications that require high stability and accuracy.

Another key advantage of black granite is its uniformly fine textures and tight porosity, which make it highly resistant to water absorption or warping from humidity. This feature is especially important for precision machine components that require high dimensional stability and resistance to deformation.

In addition to its physical properties, black granite also has aesthetic appeal, with its striking black color and fine-grained texture. This makes it a popular choice for architectural and decorative applications, as well as for precision machine components.

Overall, black granite is a versatile and highly valued material for precision machine components, offering superior strength, stability, and resistance to deformation. Its fine-grained texture and aesthetic appeal also make it a popular choice for a range of other applications.