The history of ancient art is full of tales of fakes, frauds and forgeries. One the more interesting involves a wealthy Polish nobleman by the name of Prince Stanislaw Poniatowski (1754–1833). Poniatowski was an avid fan of the arts and a well-known collector, having studied at Cambridge and spent some time in Italy visiting ruins and collectors before settling down in Rome in 1791. Gemstones had long been a favoured item by collectors as they combine the high level of skill found in sculpture with semi-precious stones, serving as "miniature masterpieces" of art. Many ancient gemstones, such as the famous Gemma Augustea, have been in circulation among the European elite since antiquity. Poniatowski had inherited a gem collection from his uncle, King Stanislas Augustus of Poland. That collection included gems of ancient and Renaissance manufacture, as well as gems made by famous contemporary engravers. Evidently Poniatowski, who was one of the richest men in Europe at that time, became quite competitive about his collecting, building up a huge collection of gemstones (~ 2600).
Poniatowski was weirdly secretive about this collection—many specialists tried to get access, but were rebuffed. He eventually published a catalog of his collection in 1831 (Catalogue des pierres graves antiques de S.A. le Prince Stanislas Poniatowski) and also circulated impressions of some of the gemstones. However, specialists at the time became skeptical of the collection’s authenticity. It seemed improbable that a single person could collect so many previously unknown ancient gemstones. Further, a shocking number (over 1700!) had artist's signatures, when in fact it is extremely rare to find a gemstone engraved with the name of its carver. The practice of adding fake signatures was a well known tactic amongst antiquities dealers for enhancing an object’s value. Further, names of engravers of vastly different art historical periods, such as Pyrgoteles (later 4th century BCE) and Dioskourides (late 1st century BCE) were attached to gemstones of suspiciously similar style, shape, and size.
Several years after his death, in 1839, Poniatowski’s entire collection went up for sale at Christie's. None of the major collectors or museums were especially interested given the rumours of forgeries. Nonetheless, many collectors eventually purchased gems from the collection, with the largest number - around 1140 - acquired by Colonel John Tyrrell, who was convinced of their antiquity. However, when he enlisted the expertise of the antiquarian Nathaniel Ogle to write an introduction for the publication of his collection, Ogle had to break the hard news to Tyrrell that they had been made in the late 18th and early 19th centuries. Tyrrell was furious, and an argument about their authenticity erupted onto the pages of newspapers and journals at the time, where it was revealed that Poniatowski had commissioned the gems from renowned Italian engravers, and then had other engravers put false signatures on them.
One aspect that is interesting about these gemstones is that the images are not copies of ancient gems (or even other ancient works of art), but rather original illustrations of mythological tales found in Classical literature—such as those found in Homer, Virgil, Ovid. Some are portrait-heads of significant cultural and historical figures Greco-Roman antiquity. Carved in styles inspired by Greek and Roman art, they are truly impressive examples of Neoclassical art. Unfortunately, because of the scandal, the Poniatowski gemstones have been largely disregarded, and are disseminated widely among collections today. The Tyrrell collection is best known because he published it along with photographs and many impressions were made from the gems, which are also in circulation. The Beazley archive is working on documenting the whole of the Poniatowski collection.
Recently, Getty curator Kenneth Lapatin did some sleuthing to determine that a gemstone depicting Mark Antony - long believed to be a masterpiece of the 1st century BCE - actually belongs to the Poniatowski collection, was actually carved by the famous 19th century Italian gem engraver Giovanni Calandrelli.
Confirming the authenticity or lack thereof of gemstones is difficult, because both ancient and modern cutters use largely the same techniques. In the case of the Poniatowski gems, the discovery of sketches and notes by Calandrelli have helped confirm their 19th century date.
Whatever the deceptions surrounding their creation and collection, the Poniatowski gems are beautiful works of high artistic quality. They are compelling examples of the reception of Greek and Roman antiquity in the European arts of the late 18th and early 19th centuries.
‘The Poniatowski Collection of Gems’, The Beazley Archive:
K. Lapatin, ‘The Getty Gnaios: A love story’, Journal of the History of Collections, fhaa049 (2021) https://doi.org/10.1093/jhc/fhaa049
H. J. Rambach, ‘The gem collection of Prince Poniatowski’, American Numismatic Society Magazine 13 no. 2 (2014), pp. 34–49. https://www.academia.edu/7592950/The_Gem_Collection_of_Prince_Poniatowski
C. Wagner, ‘Fable and history: Prince Poniatowski’s neoclassical gem collection’, in Essays on Antiquity and the History of Collecting in Honour of Arthur MacGregor, ed. H. Wiegel and M. Vickers (Oxford, 2013), pp. 145–50. https://www.academia.edu/7063064/_Fable_and_history_Prince_Poniatowski_s_Neoclassical_gem_collection_in_Excalibur_Essays_on_Antiquity_and_the_History_of_Collecting_in_Honour_of_Arthur_MacGregor_2013_145_150_eds_M_Vickers_and_H_Weigel
G. Platz-Horster, L'antica maniera. Zeichnungen und Gemmen des Giovanni Calandrelli in der Antikensammlung Berlin (Berlin, 2005).