No Crowns (Five Shillings) or Halfcrowns (Two Shillings and Sixpence) were struck in 1804.
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The Crown represented a quarter of a Pound (or Sovereign).
Halfcrowns were issued much more regularly because they were useful in change-making in the presence of a 6d (half-shilling) coin.
There were no 1804 British Sovereigns minted. The Sovereign was reintroduced into the currency in 1817.
There was no 1946 British Crown minted.
There was no 1908 British Crown (Five Shilling) minted.
There was no 1956 British Crown (Five Shillings) minted.
There was no 1963 British Crown (Five Shillings) minted.
There was no British 1907 Crown (Five Shillings) minted.
There was no British Crown minted from 1938 to 1950 inclusive.
There was no 1923 British Crown (Five Shillings) minted.
There was no British Crown minted from 1903 to 1926 inclusive.
There was no British Crown minted from 1848 to 1886 inclusive.
There was no British 1886 Crown (Five Shillings) coin minted.
There was no British 1846 Crown (Five Shillings) coin issued.