The Staffordshire Potteries is the industrial area encompassing the six towns, Tunstall, Burslem, Hanley, Stoke, Fenton and Longton that now make up the city of Stoke-on-Trent in Staffordshire, England. North Staffordshire became a centre of ceramic production in the early 17th century, due to the local availability of clay, salt, lead and coal. Hundreds of companies produced decorative or industrial items.
The boom came after the discovery in 1720 by potter John Astbury of Shelton, that by adding heated and ground flint powder to the local reddish clay he could create a more palatable white or cream ware. The flint was sourced from either the South Coast of England or France, then shipped to the Port of Liverpool or to Shardlow on the River Trent. After shipping by pack horses to the watermills local to the potteries, or to commercial flint grinding mills in either the Churnet Valley or Moddershall Valley, it was sorted to remove flint that had reddish hues, then heated to 1,200 °C (2,190 °F) to create an easily ground product. A group involving James Brindley later patented a water based process that reduced the generation of fine siliceous dust, thereby reducing the risk to workers of suffering silicosis. In the early 1900s the process was converted to grinding bone, which had a similar effect.