Copper-zinc alloy (brass) used for watchcases, copper 5 pts: zinc 1pt. Invented by Christopher Pinchbeck:
"Pinchbeck's advertisement can be found in the London Daily Post of 28 June 1738. Pinchbeck, a Toyman, was somewhat of a specialist in gimmick inventions which promised quick, cheap and easy solutions. He advertised in the Daily Post of 28 November 1732 that he had discovered 'the secret of a new invented metal which looks like gold' which he was prepared to divulge at a price."
Source for the quotation above: Matthew Craske, Plan and Control: Design and the Competitive Spirit in Early and Mid-Eighteenth-Century England, Journal of Design History, Vol. 12, No. 3, Eighteenth-Century Markets and Manufactures in England and France (1999), pp. 187-216. Published by: Oxford University Press on behalf of Design History Society.