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:
"The Royal Mint Refinery (RMR) 1 oz Gold Bar contains 1 oz of 999.9 gold. Bearing the RMR logo, this 1 oz gold bar is protected in serialised security packaging printed with a unique serial number matching the number imprinted in the bullion bar to act as a certificate."
The type of packaging described above is referred to as "in assay" by bullion dealers.
The bar is "minted" (struck using minting techniques similar to a coin, and not cast in the way that larger investment products are). | 
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