Lake Freighter James L. Oberstar Coasters Soo Locks Gifts And Collectibles! Great Lakes Marine Photo, Gifts, Collectibles for boat fans. Our Coasters pop with vivid color, making them that perfect unique gift. Images are high resolution and imprinted deep into the tile, they will not fade or peel. They can hold heat up to 400 degrees, making them perfect for coasters & trivets. They also are stain resistant and waterproof and can be washed with any cleaner. All coasters and trivets have cork backings. Due to cork backings, we do not recommend washing in a dishwasher. All coasters can be used with regular tile work and would make a great Michigan theme backsplash. Hope you enjoy the photos!