The coin shown here is a late example of a round ‘silver’ threepenny piece. Such coins were discontinued in 1945. The coin had the nickname a Joey.
The first threepenny coins were minted in the reign of King Edward VI in 1547. The threepence was made from 92.5% silver until 1920, when the silver content was reduced to 50%. The coin featured here is dated 1939 and so has the lower silver content.
The coin is small to reflect its value in silver. A silver sixpence weighed twice as much and a silver shilling twice as much as a sixpence. The relative size of some small coins is shown below.
The obverse side of the coin was a portrait of the monarch, but the reverse design was not constant, as illustrated below. The design on the reverse of this Memory Box coin was introduced in 1937. The portrait of King George VI faces left, as did that of his father. Had coins been issued for the reign of Edward VIII, his image would have traditionally faced right.
The 12 sided threepenny bit commenced in 1937 whilst production of the silver coin continued for a while. It ceased to be legal tender after 31 August 1971
Any reference to pence prior to 1971 referred to ‘old’ pre-decimalisation pennies.