Proline Decorative Concrete Systems 3SL 36" x 36" Small Seamless Sandstone Light Concrete Stamp. Sandstone is a sedimentary rock composed mainly of sand-size mineral or rock grains. Sandstone is a common building and paving material. Proline can bring you the look of natural Sandstone in a fraction of the cost. Additionally, concrete is more durable, faster to install, holds up to any conditions and can be colored to your tailored needs. Perfect inside or out, this pattern will make a wonderful addition to your home. The Seamless Texture design, an innovation of Proline, allows for easy installation. As with all our Seamless Textures, with the exception of touch up skins, handles are included for increased control.