Creamware of these potteries would have been producing creamware. Whilst Staffordshire had taken the lead, creamware came to be developed in a number of large potting centres where stoneware was already being produced, eventually replacing stoneware entirely. These included Derbyshire, Liverpool, Yorkshire (including the Leeds pottery) and Swansea. Attribution of pieces to particular factories has always been difficult because virtually no creamware was marked prior to Josiah Wedgwood's manufacture of it in Burslem. At the time manufacturers frequently supplied wares to one another to supplement stocks and ideas were often exchanged or copied. In addition, factories usually sent out their wares
American art pottery Arthur Dovey, who worked at Niloak, is often credited with inventing this swirl, but it may have been invented earlier in a different pottery altogether. There is no question that Niloak popularized the style, however, and apart from a three-year hiatus in the late 1910s, Niloak was successful until the Great Depression put sales into a slump. It struggled on for some years and went out of business in 1947. The J. B. Owens Pottery Company was founded in Roseville, Ohio, in 1885 by J. B. Owens. After moving to Zanesville, it produced art pottery from 1896 to around 1910,