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:
"Our smallest Royal Mint Refinery gold contains 1 g of 999.9 gold, an excellent choice for gifts or if you wish to start building an easily divisible portfolio. The 1 gram gold bar is presented in serialised security packaging to securely transport and preserve it. Each sealed pack is 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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