McCarter coasters are extremely absorbent. Condensation from your glass will seep 

into the porous clay coaster and take-in any liquid. No more drips or stains! Continues to 

soak-up all day. We don't know where the water goes! Normal use will render a long lasting 

coaster that will need very little care. If a stain should occur, run the

 coaster through the dishwasher. If the stain is still showing itself, apply a few drops of bleach on the surface, 

rinse with water and allow to dry. This will restore the coaster to its original condition. 

CHEERS!