Penny (Irish decimal coin) from 2002 on its own). Penny (Irish decimal coin) The decimal one penny (1p) () coin was the second smallest denomination of the Irish pound. It was first issued when the Irish currency was decimalised on Decimal Day, 15 February 1971. It was the second of three new designs introduced all in bronze, the others being a half-penny and a two pence coin. All featured ornamental birds designed by Irish artist Gabriel Hayes on the reverse. The coin originally had a diameter of 2.032 centimetres and mass of 3.564 grams consisting of copper, tin and zinc. This was identical to
Decimal Day Ireland operated within the Sterling Area, effectively a single monetary area. The Irish pound had come into existence as a separate currency in 1927 with distinct coins and notes, but the terms of the Irish Currency Act obliged the Irish currency commissioners to redeem Irish pounds on a fixed 1:1 basis, and so day-to-day banking operations continued exactly as they had been before the creation of the Irish pound (). This state of affairs continued until 1979 when Irish obligations to the European Monetary System forced them to break the historic link with Sterling. In Ireland, all pre-decimal coins, except