A Neoclassical amethyst intaglio pendant c.1820 from The Poniatowski Collection, the oval amethyst engraved with a scene from Classical mythology depicting Neptune in the form of a sea horse carrying Medusa across the sea, with a pseudo signature of the Ancient Greek gem engraver Gnaois (active 40–20 B.C.), set in a later gold mount with pearls at the cardinal points suspended from a triple looped hinged pendant fitting set throughout with half-pearls.
Prince Stanislas Poniatowski (1754-1833) was a wealthy Polish nobleman and diplomat and the nephew of the last King of Poland Stanisłas Augustus II. Following the Partitions of Poland at the end of the 18th century Poniatowski immigrated to Italy, living first in Rome and then in Florence.
He was a passionate collector and his interest in Ancient gems was sparked by a small group of Classical intaglios that he inherited from his uncle. Having the financial means to pursue this interest, he subsequently proceeded to amass a collection of considerable size and importance. In total he acquired over 2500 gemstone intaglios depicting scenes from Classical mythology but far from being the work of Classical engravers they were in fact contemporary and had been commissioned by the Prince himself. Designed and carved by some of Italy’s most revered gem engravers such as Giovani Calandrelli (1784-1853) and Luigi Pichler (1773-1854) many of the pieces bear counterfeit signatures of known Ancient Greek and Roman gem carvers. These signatures include those supposedly by Apollonides, Dioscurides and Gnaois – the latter easily discernible on our amethyst pendant. The scenes depicted are inspired by the great works of Classical literature particularly those of Homer, Virgil and Ovid and feature characters such as Hercules, Zeus, Juno and Ganymede.
During his lifetime, Poniatowski’s collection was believed to be genuine (encouraged by the Prince himself) and the most significant of its kind, however he strictly limited access to it so verification was difficult. He published a comprehensive catalogue of the collection in 1831 with this amethyst listed as number 125 and described thus ‘Neptune changé en cheval marin, et Méduse.’
After the Prince’s death in 1833 his estate was dispersed and eventually the majority of this collection came up for auction at Christie’s in 1839 at which time the deception became clear. Despite this, a large proportion of the gems sold to a Captain John Tyrrell who refuted the evidence of the Prince’s deceit, believing it impossible “that a nobleman of his high character and honour would have asserted that which he did not believe to be true”. This amethyst was one of the pieces acquired by Tyrrell and in the catalogue he published in 1841 it is listed as number 83 and the scene given a much fuller description ‘Neptune, captivated with Medusa, daughter of Phorcus, metamorphosed himself to a horse, carried off Medusa, and crossing the sea, obtained her favour in a temple of Minerva; which so irritated the goddess, that she changed the beautiful hair of Medusa into serpents.’
Since then the gems in the collection have been bought and sold and dispersed across the world. Known examples exist in museums such as the Victoria and Albert Museum, the British Museum and the J. Paul Getty Museum and the collection remains of great interest to both scholars and collectors with research still ongoing. Today these gems are valued as beautiful examples of early 19th century gem carving executed by some of Rome’s most expert engravers, thereby of interest and value in their own right as well as being part of a great 19th century forgery.
Poniatowski, S., Catalogue des pierres gravées antiques de S.A. le Prince Stanislas Poniatowski, 1830-1833
Prendeville, J., Explanatory catalogue of the proof-impressions of the antique gems possessed by the late Prince Poniatowski and now in the possession of John Tyrrell, Esq, H. Graves for the proprietor, London, 1841