Signature: [1] On portrait of Marie Louise: Isabey 1812
[2] On portrait of King of Rome: Isabey 1815
[3] On portrait of Napoleon: M. 1815 (said to be Madame Lizinka Aimée Zoé de Mirbel)
Marking: [1] GRM, an ear, in a lozenge (maker's mark)
[2] bear's head, numeral 3, in circle (unofficial Paris mark for gold, post-Revolution)
[3] lion's head in circle (Paris large excise mark for gold, 1809-19)
[4] possibly a cock, numeral 3, in vertical hexagon (Paris mark for 3rd standard gold, 1809-19)
[5] bull, numeral 3, in horizontal hexagon (Paris mark for 3rd standard gold, 1819-38)
[6] old man's head, profile to left, in circle (Paris large excise mark for gold, 1819-38)
[7, 8] indecipherable
Location of marks:
[1], [2]: inside bottom and cover, inside bezel on right end
[3], [4], [7], [8]: inside cover
[5]: on bezel, on left end
[6]: on bezel, on right end
