This two-coin set is one of the "historic" issues by the Royal Mint combining a newly released coin with a historic coin taken from circulation.
The mint says about it:
"On D-Day, 6 June 1944, more than 132,000 ground troops and 18,000 paratroopers successfully stormed five assault beaches along the Normandy coastline in France. By gaining a foothold on mainland Europe, the Allies were able to open a second front against Germany that helped turn the tide of the Second World War. This two-coin set comprises a silver Proof edition of the 2024-dated commemorative coin we have struck to mark the 80th anniversary of D-Day alongside a 1944 King George VI florin. The obverse of the latter includes Humphrey Paget’s portrait of George VI, whilst the obverse of the former features the official coinage portrait of His Majesty King Charles III by Martin Jennings."
The 50p coin is in sterling silver (0.925) and in proof grade grade, while the florin is 50% silver in "fine or better" grade.
The set comes in a black presentation box, with a numbered Certificate of Authenticity. | 
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