Architecture of Stone
Our use of stone dates back to, well, the Stone age, when humans would use stone as a tool. Stone itself has been around for millions of years and is one of the oldest materials known to man. There are three basic types of rock: Sedimentary, Igneous and metamorphic.
Sedimentary rock is produced when some of the earth's material is washed or blown around and then settles through time and under pressure to form rock. Limestone and travertine are examples which can show the formation and character of their origins.
Igneous rock is the result of magma, the molten rock beneath the earth's surface, having cooled and solidified, often trapping complex and precious minerals within its structure. Their crystals can be seen as flowing layers or may occur randomly, both giving rise to wonderful effects when the surface of the stone is cut and polished. Granite is one of the most common examples.
Metamorphic rock is formed when either of the above two rock types is put under intense heat and pressure below the earth's crust. The deeper the rock beneath the surface, the higher the grade and the greater the likelihood of colour combinations. Marble is an example. Slate, by contrast, is formed much nearer the surface, meaning its grade is low by comparison.
Man-made stone such as Terrazzo is a product of small chips of stone being poured into a cementitious binder and then polished to reveal a speckled finish.
Until the nineteenth century the UK, like other countries, tended to use stone which was local; now it mostly uses stone from abroad. More than four hundred UK quarries are still active, largely producing sandstone, limestone and chalk. These are mainly used for cement and roadstone, but also for conservation architecture, repairing buildings of an earlier period.
Stone can enrich an architectural space. It has the qualities to be smooth or rough, forming tactile and warming backdrops to a room. It can be used for structural walls, lintels, flooring and worktops.
When we work with stone on any of our projects it is very important to get a recent sample cut from the quarry. Any single quarry or source may produce considerable variations in the colour and veining of the stone that is extracted and it would be wrong to expect or look for uniformity of appearance - this is the unique characteristic of stone.
