Thank you for viewing our products. This listing is for 15 coasters (100x100x13mm) made of artificial marble, specifically Corian. These were originally samples for choosing the color of artificial marble, but they actually work incredibly well as coasters, so I purchased them previously. Since they are made of Corian artificial marble, they can be washed, and even if they get scratched, you can sand them with fine-grit sandpaper to make them look new again. The size is approximately 100x100x13mm, which is the perfect size for a coaster. What do you think? Thank you. ★This product is new and unused, but it has been stored, so there may be some minor dirt or scratches. If you are concerned about this, please refrain from purchasing. #coaster #artificialmarbleCorian #artificialmarble #Corian