NATURAL MATERIAL:The black square slate coasters are made of high-quality slate,and has a protective layer to maintain its natural color and texture,sturdy and durable. These stone coasters are reusable, durable and environmentally friendly TABLETOP PROTECTION: These slate coasters have high temperature resistance, which can prevent hot and cold drinks.So they can be used to protect the table from water rings or burns. Also prevent condensation from leaving any stains or water marks on your countertop, bar, or tabletop surface DIY CRAFT:These slate coasters are also painted with chalk diy to create unique coasters. The pattern can be erased, and can be changed at any time according to your mood. It's an interesting coaster.Let's add some fun to your life! EASY TO CLEAN:These square slate coasters bulk have a black finish, which prevents leaving imprints and makes it easier to clean.The slate coaster is easy to clean, and can be washed directly with water or wiped with a damp cloth. Not suitable for dishwashers WIDE APPLICATIONS:The slate drink coasters are ideal for hot and cold beverages, cups, mugs, glasses, goblets, photo props, and so on.It is perfect for use in the bar, kitchen, home, etc