Watch List notes:

One Hundred Pounds 2011 Jupiter - Higher, Gold One Ounce as S.4916, an unlisted type with the designer's initials IRB below the bust, the initials not normally seen on the obverse of this coin, examination of all previously sold coins on our archive database and the Spink plate coin all show no initials, so potentially a very rare and previously unrecorded type, this an extremely unusual occurrence on modern Royal Mint Gold coins. FDC in the Royal Mint box of issue with certificate number 0453

Estimate: 1800-2200 GBP