Several common differences between black granite varieties

One, according to the hardness difference:

The hardness of a stone is calculated from the Mohs scale, which is 6-7 for hard stones, such as granite; 3-5 for medium-hard stones, such as marble; and 3-5 for soft stones, such as limestone and dolomite , the hardness is 1-2.

Marble: Marble usually contains impurities. Calcium carbonate is easily weathered and dissolved by carbon dioxide, carbides and water vapor in the atmosphere, resulting in rapid loss of luster on the surface. Therefore, a small amount of pure quality, less impurities, relatively stable and durable types, Such as white marble and greenery, it can be used outdoors, while other types are not suitable for outdoor use, and are generally only used for interior decoration. The Mohs hardness is 3-5.

Granite: The hardness of granite is higher than that of marble, so it is difficult to process, but it is resistant to acid and weathering. It is not easy to weather and change, and its appearance and color can last for more than 100 years. Therefore, it is mainly used for wall foundations and exterior wall finishes. Granite is also commonly used in construction Decorative works, such as the floor of the lobby, due to its high hardness and wear resistance. Mohs hardness is 6-7.

2, the difference in chemical composition:

1. Marble: It belongs to carbonate rock. Its main component is calcium carbonate, accounting for more than 50 percent, other components include magnesium carbonate, calcium oxide, manganese oxide and 2 silicon oxide. Usually there are obvious patterns and many mineral particles.( fundamental)

2. Granite: It is mainly composed of time, feldspar, amphibole, pyroxene, olivine and biotite, belonging to silicate rock, the main component is 2 silica, accounting for 65% 75%. (acidity)

3, food difference:

1. Marble (alkaline): The mineral composition of marble is simple, easy to process, the texture is fine in most parts, the mirror effect is good, but it is rich in natural texture. Its defect is that the texture is softer than granite, and it is easily damaged by the impact of hard and heavy objects, light color Stone is easily polluted. Try to choose the color of marble floor. Marble usually contains impurities, calcium carbonate is easily weathered and corroded by carbon dioxide, carbide and moisture in the atmosphere, causing the surface to lose luster quickly. Therefore, most types of marble Not suitable for outdoor use, usually only used for interior decoration.

The color temperature of marble color makes people feel warmer and softer. Most have texture or pattern, but there are a few exceptions, with obvious grains, such as crystal white or rosin yellow.

2. Granite material (acidic): Granite has no color bars, as long as the color spot pattern, its characteristics are fine and even grains, scattered with star-shaped mica bright spots and sparkling seasonal crystals. The finer the mineral particles, the better, indicating that the structure is dense And solid. The color temperature of granite color makes people feel cooler, harder, and more wear-resistant. Most surface patterns look colorful and more vivid. After polishing, the smoothness is higher than that of marble, and there is generally no texture. It has crystals The particles are evenly distributed, but there are a few active particles, such as the magical color red, etc. The rock is hard and dense, with high hardness, wear resistance, and is not easy to be weathered and transformed. Its appearance and color can last for more than 100 years. Therefore, it is often used in architectural decoration. In the project, it is more suitable for outdoor balcony, courtyard, floor and window sill of guest room restaurant

1. Marble: The main component of marble is calcium carbonate, but the color of marble is related to the minerals it contains. The main components are calcium carbonate white, copper green or blue, cobalt light red, manganese rose red, iron yellow, strontium light Blue, graphite black and grey black.

2. Granite: The color of the stone mainly depends on the mineral composition. Generally speaking, if the content of feldspar and feldspar is large, the color of the stone will be light. When other minerals are abundant, it constitutes gray series granite and gray series granite.