Granite and marble are both stones, so there is a big difference

Granite and marble are both stones, so there is a big difference

1. Granite

Granite belongs to igneous rock, which is formed by underground magma eruption and intrusion cooling crystallization, as well as granitic metamorphic rock. With visible crystal structure and texture. The main component of granite is silica.

Because granite is stronger than sandstone, limestone and marble, it is difficult to mine.

(1) It has good decorative performance and can be applied to public places and outdoor decoration.

(2) It has excellent processing performance: sawing, cutting, polishing, drilling, engraving, etc. The machining accuracy can reach 0.5 μ M U.M and the luminosity is above 1600.

(3) Good wear resistance, 5-10 times higher than cast iron.

(4) It has a small coefficient of thermal expansion and is not easy to deform. It is similar to indium steel and is very little affected by temperature.

(5) High elastic modulus, higher than cast iron.

(6) Good rigidity, large internal damping coefficient, 15 times larger than steel. It can be shockproof and shock absorption.

(7) Granite is brittle, and it will only fall off locally after being damaged, which will not affect the overall straightness.

(8) Granite has stable chemical properties, is not easy to be weathered, and is resistant to acid, alkali and corrosive gases. Its chemical properties are directly proportional to the content of silica, and its service life can reach about 200 years.

(9) Granite is non-conductive, non-magnetic and stable in field.

Generally, granite is divided into three different categories:

Fine grained granite: the average diameter of feldspar crystal is 1 / 16 ~ 1 / 8 inch.

Medium grained granite: the average diameter of feldspar crystals is about 1 / 4 inch.

Coarse grained granite: feldspar crystals have an average diameter of about 1 / 2 inch and larger crystals, and some even reach several centimeters. The density of coarse-grained granite is relatively low.

In recent years, granite accounts for 83% and marble 17% of the stones used in Monument buildings.

2. Marble

Marble is formed from sedimentary rock and metamorphic rock of sedimentary rock. It is a metamorphic rock formed after limestone recrystallization, usually accompanied by the texture of biological remains. The particles are fine (refer to calcium carbonate), and the distribution of surface stripes is generally irregular, with low hardness.

The composition and structural characteristics of marble make it have the following properties:

(1) Good decorative performance, marble does not contain radiation and has bright colors and rich colors. It is widely used for decoration of indoor walls and floors. It has excellent processing performance: sawing, cutting, polishing, drilling, engraving, etc.

(2) Marble has good wear resistance and is not easy to age. Its service life is generally about 50-80 years.

(3) Marble is widely used in industry. For example: for raw materials, purification agents, metallurgical solvents, etc.

(4) Marble has the characteristics of non-conductive, non-magnetic and stable field.

Marble shall be divided into four categories: A, B, C and D. This classification method is especially applicable to relatively brittle class C and class D marbles, which need special treatment before or during installation.

The specific classification is as follows:

Class A: excellent marble, with the same and excellent processing quality, without impurities and pores.

Class B: the characteristics are similar to the previous class of marble, but the processing quality is slightly worse than the former; Have natural defects; A small amount of separation, gluing and filling are required.

Class C: there are some differences in processing quality; Defects, pores and texture fractures are common. The difficulty of repairing these differences is moderate, and it can be achieved by one or more of separation, gluing, filling or reinforcement.

Class D: the characteristics are similar to those of class C marble, but it contains more natural defects, and the processing quality is very different. It needs multiple surface treatments with the same method. This kind of marble involves many colorful stones, which have good decorative value.