The set features the four "Sovereign" denominations issued in 1999: half sovereign, full sovereign, double sovereign, and a "quintuple" (five sovereigns piece) gold coins. Three of them have the traditional Saint George and the Dragon reverse and are identical in appearance (the value and denomination is not written on the coin) - they only differ in size and weight, which are proportional to their value.
In place of the traditional double sovereign though (which has a nominal face value of two pounds), there is the gold version of a Rugby World Cup commemorative £2. There seems to have been an understanding at the time that the gold versions of these coins represent a double sovereign (hence the same parameters), and they are referred to as such in some sources; this is also confirmed by the fact that the Royal Mint issued no St. George type double sovereigns in the years when these coins were issued.
The set also contains a gold-plated oblong Royal Mint 1999-dated medal and a numbered Certificate of Authenticity. | 
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