A British Fifty Shillings (50/-) coin has only ever been minted once, in the year 1656. It was a milled gold coin weighing 22.7 grams and with a diameter of 30 millimetres. Only eleven examples are known to exist, and they have a current value of approximately £15,000 - £20,000 each.

The obverse of the coin depicts Oliver Cromwell as a Roman Emperor, with the inscription OLIVAR D G R P ANG SCO HIB &c PRO -- Oliver, by the grace of God Protector of the Republic of England, Scotland, Ireland, etc.. The reverse depicts a crowned shield bearing the Commonwealth arms, with the inscription PAX QVAERITUR BELLO 1656 -- Peace is sought through war, while there is an edge inscription PROTECTOR LITERIS LITERAE NVMMIS CORONA ET SALVS -- A protector of the letters, the letters are a garland and a safeguard to the coinage.

For other denominations, see British coinage