Halfpenny (Irish decimal coin) Halfpenny (Irish decimal coin) The decimal halfpenny (p) () coin was the smallest denomination of the Irish pound. It was first issued when the Irish currency was decimalised on Decimal Day, 15 February 1971. It was one of three new designs introduced all in bronze and featuring ornamental birds on the reverse. The coin value was weakened by inflation and very few were produced beyond the initial run for 1971. It was removed from circulation and demonetised on 1 January 1987. The main reason that halfpennies were issued was that when shillings were decimalised they were worth five new pence,
Coins of the pound sterling of the 20p coin has also been amended to incorporate the year, which had been on the reverse of the coin since its introduction in 1982 (giving rise to an unusual issue of a mule version without any date at all). The orientation of both sides of the 50p coin has been rotated through 180 degrees, meaning the bottom of the coin is now a corner rather than a flat edge. The numerals showing the decimal value of each coin, previously present on all coins except £2 and £1, have been removed, leaving the values spelled out in words only.