The Prism Onyx Natural is incredible! To do it justice, we only offer this in a polished finish. Both 12x24 and 24x24 inch sizes are available for larger spaces and expansive bathrooms. The HD glaze clarity is amazing on this porcelain tile. Exclusive to Carpet and Tile Mart, this porcelain collection offers incredible copies of the most popular marbles on the planet, using the latest in HD glazing technology.