These high quality stone coasters feature classic imagery from the best parts of Minnesota, perfect for any Minnesotan! They measure 4" x 4" and are 1/4" thick. While they ARE waterproof, they are not recommended for the dishwasher. The coasters have a cork backing, to prevent any scratching of furniture. We design and print these at our facility in Edina, MN. Please keep in mind that, due to the natural texture of the stone face, slight variations in images are possible.