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.

Its dimensions and appearance were the same as the British coin of the same denomination as the pounds of Britain and Ireland were pegged until 1979.

The coin was designed by the Irish artist Gabriel Hayes and the design is adapted from the manuscript Cologne Collectio Canonum (Cologne, Dombibliothek Cod.

The coin has a diameter of 1.7145 centimetres and mass of 1.782 grams consisting of copper, tin and zinc.