Rocks, ceramics, glass and even paper are some of the surfaces you can use these multi surface markers. Bright water based paint that works on smooth non-porous areas such as glass, mirrors, whiteboards or ceramics means the color can be washed off. Used on porous surfaces such as cardboard, wood or rocks, your design is there to stay! With 12 luscious acid-free inks these paint markers are ready to tackle any of your creative endeavors! For ages 8 and up.