An agate intaglio seal

'The Grief of Achilles Upon the Death of Patroclus', after Nathanial Marchant, length 3.0 cm, width 2.5 cm, height 4.5 cm.

Literature
Gertrud Seidmann and Robert L. Wilkins, 'Nathaniel Marchant, Gem Engraver', in The Volume of the Walpole Society, London, 1987, Vol. 2, as 'The Grief of Achilles Upon the Death of Patroclus', 1772-81, Fig.11
LIV. 'From a Cameo of Greek sculpture in the possession of Monsignor Ferretti; the Cameo has been broken in the middle, and is incomplete: therefore part of the Intaglio has been supplied to correspond with the subject.' Before Achilles, who is seated in an attitude of grief, stands Antilochus, leaning on a pillar; behind Achilles is a young woman in a Phrygian cap and a soldier before an altar.