Pinchbeck (alloy) Pinchbeck (alloy) Pinchbeck is a form of brass, an alloy of copper and zinc, mixed in proportions so that it closely resembles gold in appearance. It was invented in the 18th century by Christopher Pinchbeck, a London clockmaker. Since gold was only sold in 18-carat quality at that time, the development of pinchbeck allowed ordinary people to buy gold 'effect' jewellery on a budget. The inventor allegedly made pinchbeck jewellery clearly labelled as such. Pinchbeck jewellery was used in places like stagecoaches where there was a risk of theft. Later dishonest jewellers passed pinchbeck off as gold; over the years
Brass around 2%. Since lead has a lower melting point than the other constituents of the brass, it tends to migrate towards the grain boundaries in the form of globules as it cools from casting. The pattern the globules form on the surface of the brass increases the available lead surface area which in turn affects the degree of leaching. In addition, cutting operations can smear the lead globules over the surface. These effects can lead to significant lead leaching from brasses of comparatively low lead content. In October 1999 the California State Attorney General sued 13 key manufacturers and distributors