The sovereign, half-sovereign and the crown were all withdrawn from circulation in 1914 along with the phasing out of the £2 and £5 coins as the bank moved to notes for denominations greater than a pound.
As the UK moved towards decimalisation the farthing was withdrawn in 1960, the half-penny in 1969 and the half-crown in 1970.
On 15 February 1971, the Uk changed to a decimal based currency based on 1 pound equalling 100 pennies ( as opposed to a pound equalling 240 pennies or 20 shillings previously).
In fact, this was not the first attempt to introduce a decimalised currency. The introduction of the florin in 1849, of which there were 10 to the pound, marked the first steps in a process which the then government abandoned. The florin survived as a 2 shilling coin.
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