Proline Decorative Concrete Systems RS135-F 34" x 36" Random Canyon Stone Thinflex Concrete Stamp. This piece is a Canyon Stone in a random stone pattern. The stones are beautifully complimented with a Flamed Granite background. The edges of the stones are lightly chiseled. Natural stone with the durability of concrete-the true beauty of decorative stamped concrete. Color this piece with any of our easy to apply water based acrylic stains for a layered, natural stone look. The rock size in this piece vary from a smaller 9.5 Inch x 13.5 Inch to a larger 13.5 Inch x 21.5 Inch.