Does marble stain?

As a type of limestone, marble is made up of thousands of tiny grains deposited over the centuries into the stone. For this reason, different marbles mined in areas all over the world will have different densities. Some types of marbles that are exceptionally dense create a natural sealant that does not allow them to stain, while less dense marbles are more porous and susceptible to staining. Even if your marble does not stain, a spill left on its surface for a long time will etch into the stone, which is why sealing marble tiles is always recommended.