Let's make sure we differentiate quartz from quartzite. Quartz alone is a mineral of the gemstone world. It varies in color – amethyst likely the most well-known. As an engineered stone, quartz is one ingredient and the other resin. The resin fills in the pores of the quartz and makes it stronger. Quartz is mostly used for countertops, and can be found in MSI's Q-line of products.