Like many other mints, the Royal Mint issues bullion coins in precious metals, having much higher intrinsic value than their face value. The five ounce (5 oz) silver coins are denominated as ten pounds (£10).
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 commemorative gold coin celebrates the Four Generations of the Royal Family.
The Royal Mint says:
"When His Royal Highness Prince George of Cambridge was christened in 2013, it marked a rare moment in history. The happy family occasion was the first time since Queen Victoria’s reign that the monarch, her son, grandson and great-grandson were all gathered together. Despite their extraordinary royal lineage, the family are known for their down-to-earth attitude as they balance public service with decidedly ‘normal’ personal lives. As four generations of the Royal Family navigate the universal challenges and celebrations of life together, they can look forward to a whole host of family occasions in 2018. These happy events include a royal wedding, Prince George’s 5th birthday and the 65th anniversary of Her Majesty The Queen’s coronation.
The Royal Mint has struck this official United Kingdom coin to mark this important royal era. This edition of the coin has been struck in five ounces of fine silver with a 65 mm diameter. The reverse design, created by renowned heraldic artist Timothy Noad, features oak branches inspired by the Royal Badge of the House of Windsor and the initials of each generation. Just 1,000 coins are available in this Limited Edition Presentation, each presented in a Royal Mint case accompanied by a booklet."
This five ounce gold coin was issued individually, in Proof FDC grade, in a black presentation box, Royal Mint Product Code: UK18FGS5, with issue limit of 1,000 and issue price of £420.00. | 
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