Slate is a metamorphic rock that is derived from shale and composed of the sedimentation of mud, clay, and/or volcanic ash. It is characterised by its layering, which remains intrinsic to the structure of the stone, even through the metamorphic stage.
Because of this structure, Slate is almost always cleft (split rather than cut) when it is being processed. This leaves a surface that is entirely natural and has the undulations, which run through the layers of the stone on show.
Slate has been used for many centuries as a roofing material because of its minimal 0.4% water retention rate, making it certifiably waterproof. This quality also makes it a very good flooring material as well.
It is naturally most abundant in Spain and Brazil, although it is also found in many locations across the UK and Europe as well. Depending on the composition of the stone, it varies in shade, from purples and blues, through very deep greys and blacks, through to an almost green colour.
Impurities that permeate the stone's many layers can also add coppery colours, as well as beige and gold tones, but these are rarely seen within the stone's baseline composition and are far more commonly blocks of colour from when cracks have opened naturally, allowing other materials to fill the void, which then seal and go to form parts of the layers which have fallen away.
The riven, cleft edge is (almost) always the finish that a slate floor tile will come in. This is because of the relative fragility of the surface of the stone. As such, Slate has a certain charm that sets it apart from other stones which may emulate the rustic, rugged look, but which will never fully achieve the character displayed in Slate's natural cleft.
The edging will generally either be a honed edge or in some cases a tumbled edge (such as our Shepton Flagstones). Slate lends itself wonderfully to both these looks and, given its rustic feel but (generally) uniform colour, sits well in both modern and rustic schemes. For more information and a closer look at the Slates which we supply, visit our showroom!