Thanks to the ingenuity of quartz manufacturers, quartz, also known as an engineered stone, is nonporous. Similar to solid surfaces like Corian countertops, nonporous materials do not need to be sealed. This makes the maintenance of engineered stone very simple: soap, water, and a sponge. However, like any material, porous or not, nothing is completely impermeable to staining. So always clean up spills like wine, ink, or bleach as soon as possible.