Osterley Black Textured FinishThe ground floor at Osterley Park in Middlesex displays an iconic chequerboard limestone floor, worn over the years by the passage of scullery maids and footmen. Our Osterley porcelain tiles authentically replicate this aged look, but with all the practicality and low maintenance of porcelain, and an R11 slip rating for use indoors and out. Sold in boxes of 20 tiles, equalling 0. 495m.