The sovereign is a gold coin of the United Kingdom, with a nominal value of one pound sterling. Struck from 1817 until the present time, it was originally a circulating coin (see pre-decimal Sovereign) accepted in Britain and elsewhere in the world; it is now a bullion coin not intended for circulation, the intrinsic value of which is much higher than its face value.
In most recent years, it has borne on the reverse Benedetto Pistrucci's design of Saint George and the Dragon, created in 1817. Occasionally, the Royal Mint also releases one-year types with different designs, as a celebration for major events (usually Royal in nature).
There are several denominations of the Sovereign: Five Sovereigns (Quintuple Sovereign, five pounds gold), Double Sovereign, Full Sovereign, Half Sovereign and Quarter Sovereign; the current double sovereign - with face value of £2 is a continuation of the pre-decimal double sovereign, and has been issued as a decimal coin since 1974.
The designs of all denominations are identical, as - according to tradition - this type of coin has never had its value and denomination spelled out anywhere on the coin. The various denominations are only distinguished by size and weight, these being exactly in proportion to their face value. Since 1817, the composition has always been 22 carat (91.67%) gold.
In 2017, the Royal Mint celebrated the 200th anniversary of the Sovereign denomination by a return to its original design by Benedetto Pistrucci. Used only between 1817 and 1820, this rendition had the figure of St George slaying the dragon surrounded by the Garter of The Most Noble Order of the Garter - an order of chivalry founded by King Edward III of England in 1348. The Order of the Garter is dedicated to the image and arms of Saint George, England's patron saint.
These coins are in Proof FDC grade only, issued in sets and not individually. | 
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