William Cookworthy (1705—1780) was an 18th century Quaker scientist and entrepreneur, with wide-ranging interests. He was the first person in Britain to discover how to make hard paste porcelain, and he discovered and exploited china clay deposits in Cornwall.
William Cookworthy was born on 12 April 1705 in Kingsbridge, Devon, the eldest child of William Cookworthy, a Quaker weaver. His father died when he was 13. At the age of 15 he was taken on by Sylvanus Bevan, a London apothecary, but because he could not afford the apprenticeship fees he never qualified as an apothecary himself. Around 1726 he came to Plymouth, where he lived for the rest of his life, and set up as a manufacturing chemist under the name of Bevans and Cookworthy. In 1735 he married Sarah Berry, with whom he had five daughters, but she died ten years later. He died on 17 October 1780.