Ironstone china was first made in 1813. It gained its greatest popularity during the mid-nineteenth century. The heavy, durable, off-white pottery was made in white or was decorated with any of hundreds of patterns. Much flow blue pottery was made of ironstone. Miles Mason, the first maker of ironstone china, decorated it to resemble porcelain patterns that were popular in England, Europe, America, and Asia. Some of the decorations were raised. Many pieces of ironstone are unmarked, but some English and American factories included the word Ironstone in their marks. Additional pieces may be listed in other categories, such as Chelsea Grape, Chelsea Sprig, Flow Blue, Gaudy Ironstone, Mason's Ironstone, Moss Rose, Staffordshire, and Tea Leaf Ironstone.