Granite is a common type of felsic intrusive igneous rock consisting essentially of quartz, alkaline feldspar and mica.
It is widely used in construction since prehistory, thanks to the tenacity of the material and its resistance to erosion, compared to other types of rock (especially limestone that is fragile and soluble).
Traditionally it was a stone very used in the antiquity and the work with her, by its hardness, was considered the most painful of all.
At the moment it is no longer used as a structural element but for decorative purposes that take advantage of its characteristic drawings and colors.
Granite has been widely used as a coating on public buildings and monuments and, in extreme temperature zones, required for its impermeability.
With increasing acid rain in developed countries, granite is replacing marble as monumental material, as it is much more durable.
Polished granite is very popular in kitchens because of its high durability and aesthetic qualities.
It has a very high density that oscillates between 2.6 and 2.7 g / cm3 and high hardness (7 on the Mohs scale).
It has high mechanical resistance and high chemical resistance.
Also called travertine marble. It is the name of a sedimentary rock of partially biogenic origin, formed by deposits of calcium carbonate and often used as an ornamental stone in construction, both exterior and interior.
Most of the monuments and churches of ancient Rome are built with travertine.
It does not have high density since it is essentially porous and its degree of hardness is low (3 in the scale of Mohs).
It is a compact metamorphic rock formed from limestone rocks that, subjected to high temperatures and pressures, reach a high degree of crystallization.
According to the place where it is extracted it can also be magmatic, hydrothermal and sedimentary.
The basic component of marble is calcium carbonate, whose content exceeds 90%; the other components are those that allow you to have a great variety of colors and define their physical characteristics.
It is mainly used in construction, decoration and sculpture.
It is a high density material (2.6 to 2.8 g / cm³ variable depending on the aggregates and proportion that compose it) and low to medium hardness (3-4 on the Mohs scale).
It has a multitude of compounds, where the most important is calcium carbonate. It also contains dolomite, quartz, micas and serpentines.