Sarana Tile lists Porcelain Dark Grey as a 10" x 12" matte porcelain mosaic. Sarana supplies it with a matte face that holds light rather than throwing it back. On the residential side that covers kitchens, entry foyers and open-plan living areas. On commercial jobs it turns up in retail floors, restaurant dining rooms and hotel lobbies. The nominal size is 10" x 12", listed metrically as 30x26cm. Each sheet covers roughly 0.84 sq ft. Sarana catalogues it in Volume 8 on page 12. It arrives mesh-mounted, so the spacing holds while the sheet is set and it trims down to meet a corner or a niche. Sarana prices it by the sheet.