Jean-Pierre Droz

He was employed by the prominent English manufacturer and business man, Matthew Boulton (1728 - 1809) to improve Boulton's coin and medal quality. However, he worked there for just two years. In 1789, Droz devised a collar used to engrave the sides of coins and ensure a circular shape, and though it was unsuitable for large numbers of coins, it remained in use at the Soho Mint.
He was a member of the Royal Birmingham Society of Artists. Provided by Wikipedia