Quartz Countertops are made from one of the hardest minerals on the Earth, natural Quartz Crystals. About 90% of the surface is ground up Quartz Crystals combined with about 10% epoxy binder (percentages range depending on the brand). This creates a nonporous countertop surface that is twice as strong as Granite. Quartz countertops are also heat and stain resistant and are vertually mainance free with no annual sealing required. The warrenties vary depending on the selection of brands, they range from a 10 year Warrenty to a Lifetime Limited Warrenty.