The Royal Mint of the United Kingdom, which makes the country's circulating coinage, is also very active in the bullion coinage space and issues many bullion coins which are legal tender.
Additionally, it also makes bullion which is not legal tender and is targeted at investors and not at coin collectors - such as this one.
The Royal Mint says about this product:
"This is the largest silver bar available in our Britannia bar range and contains 100 troy ounces of 999 silver. The design is a new interpretation of Britannia, designed by The Royal Mint’s Coin Design team and brought together by Principal Designer Jody Clark."
The bar is "minted" (struck using minting techniques similar to a coin, and not cast in the way that large investment products usually are). | 
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