The beauty of stone floors: types, textures and options for architecture
The study of rocks allows us to understand the formation of our earth. Its types, the designs formed, the layers, all tell the story. Along with the atmosphere and the hydrosphere, the lithosphere is one of the major parts of the earth system, supporting the biosphere. This outermost solid layer on the planet is made up of rocks and soils; as for rocks, there are several ways of classifying them. The most common is to separate them based on their formation processes, such as igneous, sedimentary or metamorphic. While sedimentary rocks make up about 5% of the earth’s crust, the remaining 95% are igneous or metamorphic rocks.
Due to their durability and strength, as well as their varied designs and colors, stones have been used as building and cladding materials for hundreds of years. For floors, stone remains a noble and elegant option, which in addition to having high thermal inertia and structural stability, has a pleasant texture to the touch.
Igneous or magmatic rocks come from the solidification of magma and create very resistant geological formations with a high level of hardness. For soils, the most commonly used are granite and basalt:
When the magma cools at depth, it gives rise to so-called plutonic or intrusive rocks, such as granite. Granite is mostly composed of quartz, mica, and feldspar minerals, although it can include other minerals as well. Depending on the location of the rock on the globe, its colors may differ. As a floor material, it absorbs little water and allows the construction of large-scale floor parts, which can be polished or left textured.
Basalt is a product of the partial melting of the Earth’s upper mantle, a material from vast lava flows. It is a hotter magma with less silica than granite, which makes it more fluid, allowing it to rise more easily to the surface of the Earth. When this magma comes into contact with the conditions of atmospheric pressure and temperature, it cools more quickly, developing a homogeneous texture and generally a darker color. For floors, this is a very durable option for indoor and outdoor environments.
Sedimentary rocks are formed by the assembly of debris, called sediments, from the fragmentation of other rocks. This occurs under relatively low temperatures and pressures, precipitated by the decomposition of pre-existing rocks followed by transport and deposition of debris or, less frequently, by chemical build-up. These rocks are generally porous and permeable. For soils, sandstone and limestone are the most commonly used rocks:
Sandstone results from the deposit of sand which, after a process of compaction and cementation, turns into rocks. The colors of the sandstone therefore vary between yellow and reddish. The surface is very rough, which makes it slip-resistant and heat-resistant, and it is often used outdoors.
Limestones are sedimentary rocks formed by the accumulation of microorganisms (mainly cyanobacteria), mainly in ancient marine environments. On soils, limestone has a silkier texture and colors that vary from gray to pink and blue. It is mainly used in outdoor spaces.
Metamorphism is a process that involves changes in the mineralogical composition, texture and structure of a rock, occurring primarily in the solid state. Metamorphic rocks result from the transformation of sedimentary or igneous rocks by physicochemical processes due to humidity, temperature or pressure inside the lithosphere. For use on floors, rocks traditionally used include quartzite and marble:
Usually white or gray in color, quartzite is composed almost entirely of quartz, formed when quartz-rich sandstones are subjected to an increase in pressure and temperature. It is an extremely hard and waterproof stone.
Marble is formed when limestone is subjected to higher pressure and temperature conditions and is mainly composed of calcite and / or dolomite. The marble floor is a very elegant option. But since it is more permeable than granite, it can easily end up staining and wearing out in high traffic areas.
Slate is created from clay under high pressure and temperature, and is formed from thin, very resistant lamellae. Its appearance is quite homogeneous, ranging from shades of gray to black, with some greenish tones. For exterior floors, it should be used with care, as it can become slippery and because it retains more heat than pale stones. Another important issue to keep in mind when working with the material is that it flakes more easily than other stones.
Check out other examples of stone floors, indoors and out, in this My ArchDaily folder.
- SeÃ§Ã£o de Materiais DidÃ¡ticos do IGc-USP (Instituto de GeociÃªncias da Universidade de SÃ£o Paulo. https://www.archdaily.com/964775/the-beauty-of-stone-floors-types-textures-and-options-for-architecture
- PÃ©rcio de Moraes Branco. ServiÃ§o GeolÃ³gico do Brasil – CPRM. Rochas. https://www.archdaily.com/964775/the-beauty-of-stone-floors-types-textures-and-options-for-architecture