Like many other mints, the Royal Mint issues bullion coins in precious metals, having much higher intrinsic value than their face value. The five ounces (5 oz) gold coins are denominated as either ten pounds (£10) or five hundred pounds (£500).
The coins are legal tender but are not intended for circulation. They are targeted at bullion investors or collectors who appreciate the special editions as pieces of art. The coins are typically "one-year" types usually issued in parallel with smaller denominations with the same reverse designs.
This gold five-ounce coin denominated as £10 is part of the Tower of London Collection coin series by the Royal Mint.
The Royal Mint says:
Starting with The Legend of the Ravens, the collection continues in 2019 with coins featuring The Crown Jewels, Yeoman Warders and The Ceremony of the Keys. Together the coins tell the story of this mighty stone fortress and the ancient ceremonies that still take place within these walls.
History comes alive at the Tower of the London. From Traitors’ Gate to the Bloody Tower, within its stone walls echoes of the past are everywhere. Once home to kings and queens, lions and bears, its most famous residents are the ravens.
The Ravens of the Tower of London is a group of at least six captive ravens which live at the Tower of London. Their presence is traditionally believed to protect The Crown and the tower; a superstition holds that "if the Tower of London ravens are lost or fly away, the Crown will fall and Britain with it". | 
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