Ooly Marvelous Multi-Purpose Paint MarkersRocks, ceramics, glass and even paper are some of the surfaces you can use these multi surface markers. Being water based, painted 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 endeavours! 12 Water based paint