Q:  What is Limestone Tile? 
A:  Limestone is the results of millions of years of seashells and bones of sea creatures settling on the ocean floor and is appropriately called a sedimentary stone.   The calcium in the shells and bones combined with the carbon dioxide in the water to form calcium carbonate, the basic mineral component of all limestone.  As layers of earth covered this deposit of calcium carbonate sediment, pressure for the weight of the layers pressed the deposit into limestone rock.   Most limestone is hard and suitable for all interior residential applications, while some limestone is extremely hard and can be used for exterior or heavy commercial applications.