Numerous factories, steelworks, collieries, and potteries were closed, including the renowned Shelton Bar steelworks. In 1887 East Liverpool boasted 21 general ware potteries which employed 2,558 operatives. Truro's importance increased later in the 19th century, with an iron-smelting works, potteries, and tanneries. The contemporaneousness of stone walls and excavated potteries was not established. These artifacts consisted of some very fine painted potteries. Copper sulfate can be used as a coloring ingredient in artworks, especially glasses and potteries. During his youth, he contributed to his family by carrying clay for use in potteries. The ancient Lapita potteries date to 1500 BC. The long "Galerie Campana" displays an outstanding collection of more than one thousand Greek potteries. As a result of this demand, tiles dominated the output of the Iznik potteries. As with other potteries, the designs of prints were very often copied. The technique was copied by other British potteries. One of these potteries is known to have existed on Loom Lane. Tunstall shares in the industries of the Potteries. Foremost of the pioneers of creamware in the Staffordshire Potteries was Thomas Whieldon.