In the course of examining some pattern or trial coins produced by the Royal Mint during the 1850's four were found to be manufactured from aluminium bronze. As aluminium metal only became available in moderate quantities from about 1855 these coins are amongst the earliest examples of the use of this metal. The application was certainly prompted by the Mint Master, the chemist Thomas Graham, who was familiar with contemporary developments in the extractive metallurgy of aluminium in France.