RUBBER DOOR MATS - larger stones using rubber doormats in a mold. Two different sized rubber mats - a mold for each mat. use steel mesh to reinforced the stone because it is so big. When casting fill one layer with concrete in the mold, then put steel mesh in and another layer of concrete. Pat down the rubber mat up side down. Leave to harden for two days then take apart the the mold and remove the rubber mat To get a nicer finish use a rotating wire brush to get rid of the casting flash.