An amethyst set in high-quality, gold-plated silver lay buried for about 600 years in the silt of an old ditch near Kolo Castle in Opole Voivodeship in southwestern Poland.
Archaeologists speculate that an aristocrat visiting the medieval castle lost the piece. The find was likely part of a brooch or possibly a crown, though the latter is less likely. Lech Marek, an archaeologist at the University of Wrocław and head of the excavation team, told Live Science that he considers it a unique artifact.
Marek and his colleague Beata Miazga wrote in their report that while medieval jewelry is often found in hoards or tombs, this piece came from a more everyday context.
Kolo Castle was established in the early 13th century as a fortress and ducal palace, and it also served as a customs house controlling the transport of timber. The original owner, Duke Bolesław III of Brzeg, later sold Kolo to wealthy knights. In 1443, the castle was destroyed during the civil wars in Silesia. In 2010, Marek and his team began archaeological excavations at the castle ruins. Since then, they have uncovered numerous military artifacts, cavalry equipment, and ceramics dating to the 14th and 15th centuries.
Using Raman spectroscopy — which identifies molecular composition by illuminating a sample with a laser — the team confirmed the stone was amethyst. X-ray fluorescence analysis showed the metal was gold-plated silver.
“Due to its symbolic significance, accessibility, and aesthetic qualities, amethysts were popular in the Middle Ages,” Marek said. People at the time believed amethysts could protect their owner from drunkenness, poison, gout, bad dreams, betrayal, deceit, captivity, blindness, witchcraft, and choking. They also symbolized modesty and faith.
“In the complex medieval game of symbols, the choice of gemstones for jewelry always had a profound reason. If a stone was believed to possess supernatural powers, its value quickly increased,” Marek explained.
It remains unknown who lost the stone or how, but researchers have no doubt that it belonged to someone of high status. The findings were published in the journal Antiquity.
