2021 Britannia Premium Executive UK 1kg One Kilo Silver Proof Coin - Low Mintage of 40. Complete with the Royal Mint Box and Certificate of Authenticity.The first time a separate design has been released for the Premium Exclusive editions in the collection. The item "2021 Britannia Premium Executive UK 1kg One Kilo Silver Proof Coin" is in sale since Monday, August 9, 2021. This item is in the category "Coins\Coins\British\Proof Sets/Coins\2000s". The seller is "jos-8558" and is located in Plymouth, Devon. This item can be shipped worldwide.