1826 Silver Half-Crown 32mm (13.76 grams) 0.925 Silver 0.4205 oz. George IV (George Augustus Frederick; 12 August 1762 – 26 June 1830) was King of the United Kingdom of Great Britain and Ireland and King of Hanover following the death of his father, King George III, on 29 January 1820, until his own death ten years later.