The British pre-decimal halfpenny coin (abbreviated as ½d), usually simply known as a halfpenny or half penny, was a unit of currency that equalled half of a penny or one four-hundred-and-eightieth of a pound sterling (there were 20 shillings to a pound, and 12 pence to a shilling so one pound was equal to 240 pence, so 480 of these coins made up £1).
Bronze coins of these specifications were introduced in 1860 to replace earlier larger copper halfpennies. Between 1860 and 1895, the half penny had the third Britannia design on the reverse, and Queen Victoria's "Bun Head" effigy. In 1895, the reverse was updated to the fourth Britannia design, which was a simplified version of the earlier design; it was issued until 1936.
In 1937, the Britannia type was discontinued in favour of the new halfpenny issue of King George VI. Both the new obverse and reverse were designed by Thomas Humphrey Paget. The striking reverse design shows Sir Francis Drake’s ship, the Golden Hind.
The denomination ceased to be legal tender in 1969 in the run-up to decimalisation, even though the new decimal currency featured a (much smaller in size) decimal halfpenny between 1971 and 1984.
With decimalisation under way already, the 1970 issue was not intended for circulation; moreover, the halfpenny was already demonetised anyway. The 1970 halfpenny coins were minted for souvenir purposes only and distributed in mint sets commemorating the changeover to the new decimal currency. | 
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