These hand-printed, vintage-inspired coasters are crafted of tumbled Italian Botticino marble, making each coaster truly unique. Each measures approximately 4" square and is cork-backed to protect your surfaces.Studio Vertu is the first and the finest in authentic marble giftware. For over 20 years, its innovative design approach has produced enduring art objects that are both decorative and functional. The unique, unearthed, and ancient look of the product is the result of combining hand-made processes with natural tumbled marble. Studio Vertu is proud to continue in the time-honored tradition of creating art with stone.