Made of sturdy stoneware clay coated with high fire glaze , lead free & food safe glaze With cork sheet on the back side to avoid scratching surfaces. Measurement : 10 cm ( 4 inches ) This listing if for Set of Four Coasters PACKAGING & SHIPPING: Each item is carefully wrapped & shipped in HEAVY DUTY cardboard box. However, if you receive an item & it is damaged , contact me & I will sort it out. Set Of 4 Handemade Stoneware Coasters Drink Coasters, Pottery Coasters Ceramic Coaster