Marble is a rock formed from the recrystallization of limestone under high pressure and high temperatures within the earth. During the process, other minerals are introduced into the structure, which are responsible for the beautiful colours of the marble. Marble countertops come in various colours like white, black, yellow, red and green. A marble countertop is scratch and stain prone, as it is not as hard as a granite surface. It is not preferred in the kitchen but works well in bathrooms and in some furniture applications.