Granite is an igneous rock, formed mainly by crystallization of once molten material under conditions of extreme heat and pressure. Commercially, various stones of volcanic origin with different characteristics from true granites, such as pegmatite, diorite, larvikyes and syenites, are also sold as �granites�. The properties of granite, that make it an ideal stone surface, are in its hardness and inherent resistance to acid. Granites are not attacked by acids normally present in foods and cleaning products. Yet granite is a porous stone and therefore requires proper scaling with silicone based impregnator to prevent staining.