Obverse: full-length draped figure of Temperance, seen from behind in three-quarter view, with her head in profile to the right. She walks away from the viewer and holds what appears to be a bridle in her outstretched right hand.

Reverse: full-length figure of Prudence, scantily draped, in three-quarter view. Her head is janiform with a bearded male in profile to the right and a female head in profile to the left. Her right arm is raised and a snake is entwined around her left arm.

The intaglios are imitations of antique figures.

There are nine similar carnelian intaglios from the same hand recorded in the 1830 Windsor inventory of jewels. All the pieces are after highly popular and frequently copied ancient prototypes. They are all similarly shaped and have identical late 18th century mounts.

The intaglio is from the collection of Consul Joseph Smith of Venice and was acquired by George III with the Consul’s paintings, drawings, books, manuscripts and medals in 1762. Whilst the gem was part of Consul Smith’s collection it is unlikely that it was executed in Venice; engravers capable of such high-quality work were found only in Rome. The group may tentatively be attributed to Anton Pichler (1697-1779) or Carlo Costanzi (1703-81). Both were Roman gem-engravers of great repute; Costanzi was particularly famous for his copies after the antique - he is known to have engraved the head of Antinous several times - ‘and none better’ - according to one contemporary.

Text adapted from Ancient and Modern Gems and Jewels in the Collection of Her Majesty The Queen, London, 2008