2013 was the first year that the silver Britannia coin was minted in fine silver. Since their introduction in 1997 the silver Britannias were minted in 0.958 but now they are 0.999 fineness.
In 2013, the purity of the silver Britannia changed from 0.958 fineness to is 0.999 fineness.
Here is an oxymoron. A silver Britannia coin which is not a Britannia silver coin. Yes, the British Royal Mint, in their infinite wisdom, have changed the alloy of the silver bullion Britannia coin from 958 parts per thousand fine silver to 999 parts per thousand 0.958 fine silver is known as Britannia silver, and was first introduced in 1697 partly to deter clipping of silver coins.
Ever since the Royal Mint started making silver bullion Britannias in 1998 (there were proof ones in 1997), they have always been made of Britannia silver. As far as we know, the Royal Mint have not publicly stated the reason for the change, but we suspect it may be for export markets, which are probably more important for the Mint than the domestic market. The change could just be to save costs, as the blanks for the new coins will not need to be alloyed, cutting out a stage in production. Unfortunately the Britannia has also faced production to a much lower quality, with many collectors being disappointed at the inferior finish.
This year, in addition to the change in purity, the proof coin has a different reverse design from the bullion coin. We believe having a different design for the proof version is to further differentiate between the proof and bullion versions, encouraging more collectors to purchase both.
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From 1998, as with all British coins, the obverse design changed to the fourth definitive UK coin portrait by Ian Rank-Broadley, showing a more mature likeness of the Queen.
The reverse of this coin is the classic standing Britannia by Philip Nathan.