Mary (1542-1567), Gold Ryal or Three Pounds, 1555, ‘jewelled’ top arches to crown, interior shaded to left, 7.21gm (Murray B-1, and same dies as Christie’s, 24 Jan. 1978, lot 61; H. Hird Sale, lot 88, and ‘Dundee’ lot 121, same rev. die; S. 5397). Has been extracted from a mount, fields smoothed and portrait lacking detail, otherwise fine and very rare (£1000-1200)

Experts in the British Museum have declared the coin genuine, despite its weight which should correctly be nearer to 7.6gm