Our clay coasters are extremely absorbent. Condensation from your glass will seep 

into the porous clay coaster and soak up any liquid. Normal use will render a long lasting 

coaster that will need very little care. After several years, if a stain should ever occur, run the

 coaster through the dishwasher. This will restore the coaster to its original condition. 

The felts will need to be replaced. These are easy to find at any hardware store or drugstore. If you would like 

some of the original felts, you can send your address to my email box and I gladly mail back a new set.