Here it is:
Ireland, 1 penny, 1978 (KM #20)
This coin is meant to circulate interchangeably with the British penny featured on December 31. Before Ireland adopted the euro in 2002, British and Irish coins enjoyed the same intermixing relationship that the American and Canadian coinage experience. Both are sized the same and are worth about the same, so they tend to cross the border frequently. One or both parties finds this to be a minor nuisance, but neither nation is bothered enough to change their coinage. When I was in the British Isles in ’95, I do recall seeing some Irish coins in the UK and British coins in Ireland. Now that the Irish use the euro, the British and Irish coins no longer cross-circulate.
The Irish penny was minted in bronze from 1971 to 1988, and is now demonetized. Today’s coin has a mintage of 25,746,000.
Weight 3.56 g
Diameter 20.32 mm
Thickness 1.47 mm
Engraver Gabriel Hayes (reverse)