Shaped coins – shapes that is other than round – are nothing new. The Chinese, as with so much else, were there well before western Europe, while for England the Civil War siege pieces of the seventeenth century are an early example of experimentation with this idea. Britain had to wait until the 1930s, however, and the issue of the 12-sided threepence for its first multi-sided coin of regular issue and thereafter there was much more to come from many other countries.
The idea to issue the world's first equilateral-curve heptagon as part of Britain's new decimal currency came originally from H. G. Conway, the technical member of the Decimal Currency Board who was at that time President of the Institute of Mechanical Engineers. The item illustrated here, which is inscribed with his name, is a trial piece from very early in the process of development. The fifty pence has since become an extremely popular coin and it is only right that on at least one coin the unsung hero of its introduction is celebrated.