Limestone is a sedimentary rock composed of mainly calcium carbonate. Natural limestone had originally been deposits on shallow sea beds, so they could carry certain visible fossil patterns. Limestone color ranges from white, blue, beige cream yellow to gray, with many variations of ivory and light gold usually considered most popular for countertop fabrications. Popular finishes are honed ("matte"), polished and tumbled. Tumbled limestone is mainly for paving applications, while polished and honed limestone slabs are commonly used in flooring and wall covering. Additional limestone uses include kitchen, bar and vanity countertops, tub surrounds, desks, fireplace carvings and other architectural and building applications such as sills, moldings, columns.