Natural stone and Silestone® are composed of quartz and silica. Quartz is one of the hardest naturally occurring elements found on the earth and Silestone® is 93% quartz, which is much higher than some, if not all, natural stones. These elements are bonded together with resins and colorfast pigments to assure consistency in coloring with the added features of stain resistance, heat resistance and significantly less susceptibility to cracking.