Ironstone china, type of stoneware introduced in England early in the 19th century by Staffordshire potters who sought to develop a porcelain substitute that could be massproduced. The result of their experiments was a dense, hard, durable stoneware that came to be known by several namese. g. , semiporcelain, opaque porcelain, English porcelain, stone china, new stoneall of which were