Watch List notes:

Nelson, Alderney, Elizabeth II, five pounds, Anniversary of the Death of Nelson, bust r., wearing tiara and robes, rev. Nelson before ships, five inlaid blue stones (possibly sapphires) below, wt. 50.58gms., in case, mint state
Appears to be struck in gold. Testing to follow with estimate appraised as appropriate.
(Estimate: 100-150 GBP)