I had some plywood, 5/8 left over from other projects so used that. I bought some ceramic tile on sale at HD for $10.89 for 11 piece box. Wanted a darker color but could not pass up the price. Was going to make it square but cut off corners looked too good. The HD where I bought the tile no longer cuts . I have a skil saw and masonry disc from other projects. Set the blade to cut 1/16 in at time with some water, surprising it worked. Set the tile with silicone adhesive sealer, held down with railroad rails. Used straight cement for grout, had it on hand left over from other projects. I know one thing it sure is heavy. Here a pix, kind of crude but cheap.