... etc,3-Available Color: Yellow, Rusty, Black, Grey, Green, Mixed color and so on4-Size:100x100mm, ... from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional ... floor tiles and other purposes. Slate is frequently grey in color, especially when seen in masse covering ... slate from North Wales can be found in many shades of grey, from pale to dark, and may also be ...