These coasters are made from materials that would otherwise be discarded, cutting down on waste! We don't skimp on quality though, these coasters are made with three layers of quality calfskin and backed with cork. The designs are hand-tooled and hand-painted by our resident artist. Each set comes four different colors. Primarily decorative, these coasters have been sealed against heat and moisture, so they may be used, though some mugs with sharper edges may leave an impression.