Marshalls Tile and Stone Interiors Rustic Black Slate Tiles have a marked riven surface creating a rustic charm. These tiles are readily available in a variety of sizes including the Marshalls 3-Way Opus pattern. Slate is a fine grained rock formed from layers of shale and clay deposits, these layers can be detected in the delicate tracery of its texture. Why not take a look at the other enchanting colours available in the Marshalls Tile and Stone Interiors Rustic range? These tiles offer enormous potential for fascinating floors and walls, both inside and out.