The main mineral components of marble are pyroxene, plagioclase, a small amount of olivine, biotite, and trace amounts of magnetite. It has a black color and structure, and after billions of years of aging, it has a uniform texture, good stability, and high strength, which can be maintained under heavy loads. Suitable for industrial production and laboratory measurement work.

Characteristics and advantages of marble square box

1. The marble square box has a dense organizational structure, smooth surface, and low roughness values;

2. After long-term aging, the internal stress of marble disappears, the material is stable, and it will not deform;

3. Acid resistant, alkali resistant, and magnetic resistant;

4. Will not get damp or rust, easy to use and maintain;

5. Small coefficient of linear expansion, less affected by temperature;

6. After collision or scratch on the working surface of the square box, only pits will be generated, and no protrusions or burrs will be produced, which has no impact on the measurement accuracy.

Specific gravity: 2970-3070kg/m3

Compressive strength: 245-254kg/mm2

Elastic wear: 1.27-1.47N/mm2

Linear expansion coefficient: 4.6 × 10-6/℃

Water absorption rate 0.13%

Shore hardness above HS70.

Accuracy levels of 000, 00, 0, and 1 are ideal tools for marking and inspection in processing enterprises.