Coasters come either round or square and typically 4 to 4.5 inch dia. or sq. Round coaters may be of different woods such as English Walnut for Turtles, Black Walnut for Tree of Life, Owls and Dog Paws with Piglets obviously in Maple. You may also find some in Cherry, Sassafras, Butternut or Oak if you are lucky. Square coasters are usually a mix of the woods detailed above.