The choice of natural stone
It is important to choose the right natural stone. Different kind of stone is used for rock gardens or grass areas. Different stone will be used for outdoor paving, different for indoor paving etc. Raw natural stone can be used for its decorative effects, but that is even more true for worked stone. Natural cladding stone, without any surface treatment, can be a highlight of the interior, as well as polished stone, that can furthermore be impregnated in order to make it completely non-absorbable. Granite, marble, sandstone, slate, onyx, travertine and others are the most often used natural stones. Natural stone is mined all around the world. An interesting fact is that some kinds of stone can be mined in the same form on different places on the planet but other kinds are typical for a certain locality and cannot be found anywhere else. For example, the deposits of red granite from Slivenec, that was used on many Prague monuments, are practically depleted. That complicates the renovation of the parts of these monuments that are made of stone.
It is important to keep in mind, when choosing stone for a particular purpose, that each kind of stone is suitable for a different purpose. The physical properties of material are vitally important. Granite, marble, sandstone, slate, marlstone, gneiss, travertine, porphyry, quartzite, but also semiprecious stones, are the most often used materials.
The use of marble has the longest tradition – it was possible to work it with bronze tools. Marble is created by the change (metamorphosis) of limestone. The re-crystallization of calcite in the Earth’s crust happens by the influence of high pressure. Limestone created by the sedimentation of particular layers has typically rich patterns and you can often find fossils in it. Polished marble can be also used as a wall painting. It is often used in the interiors, where it preserves its lustre and no patina forms on it during time due to the climate. But if patina is what you want, do not worry to use marble outdoors.
Granite is a coarse-grained igneous rock, very hard, chemically resistant and easily polished. It is used as a construction material and cladding stone in interiors and exteriors. It is ideal for its toughness – for example, in the form of kitchen countertops, mantelpieces and fireplace cladding, or even in the form of grilling stone slabs.
Sandstone is a durable and widely used material. Mainly used for paving and wall-cladding. Its durability gained an irreplaceable position for sandstone. The variety of colours of sandstone enables different combinations and creation of a colourful ambience.
Slate is very attractive to look at. Again, it can be used for cladding or paving, but also for cut roof tiles with extreme durability. Slate is also typical for its palette of colours and sizes. Some kinds of slate beautifully shine and change colours in the sun.
Quartzite is natural stone of extreme hardness. It will come to the forth especially in the form of paving or cladding. It is mainly used in the exteriors. Sometimes can be found also in the interiors in the form of floor tiles, staircases, wall-cladding, fireplace-cladding, but also windowsills.
It would be absolutely wrong to think that natural stone is an expensive material for a handful of chosen ones. Its higher price is compensated for by its extreme durability and lifespan. The supplier is also very important – their locality and price policy. Also, the source of their material. It would be of course difficult to compare the price of natural stone for wall-cladding with prices of concrete imitations of stone (artificial stone). Stone has an irreplaceable function for example in the architecture of cemeteries. Artificial stone is easily recognizable from the natural at the first sight. It is concrete, after all.