The halfcrown (or half crown) was a denomination of the pre-decimal Pound Sterling coinage worth one-eighth of a pound, or two and a half shillings (a full crown being defined as five shillings), or 30 pence. In sums, it was abbreviated "2/6" (pronounced "two and six" - two shillings and six pence, a full shilling being twelve pence). The half crown was first issued in 1549 in the reign of King Edward VI. The denomination was struck in silver for most of its existence, until it was debased to copper-nickel in 1947; so, all half crowns issued in the name of Queen Elizabeth II were in base metal.
This type of half crown was introduced as part of the first coinage of the Queen's reign, replacing an earlier design struck during the reigns of her father and grandfather. It has an updated reverse depicting the Royal Coat of Arms differently, and an obverse featuring the Queen's first definitive effigy.
The half crown was demonetised - ahead of other pre-decimal coins - on 1 January 1970, the year before the United Kingdom adopted decimal currency.
With decimalisation under way already, the 1970 issue was not intended for circulation. Coins were minted for souvenir purposes only and distributed in mint sets (in proof grade), at a point in time when they were not legal tender anymore. | 
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