According to the National Museum of Prague, the fake and synthetic stones were found after its permanent gem collection was audited.
“What we have is still a sapphire, but it is not a natural stone as was documented when the museum gained it in the 1970s. It was artificially created so it does not have the value we thought it did,” Ivo Macek, head of the museum’s precious stones department said, in an interview with Radio Praha, Prague.
“It was acquired for CZK$200,000 (AU$12,354) and today it would have been worth tens of millions. And what we thought to be a 5-carat diamond was in fact plain glass given a diamond cutting.”
Half of the museum’s rubies are also reportedly synthetic. The museum’s deputy director Michal Stehlík added the museum was now trying to determine how the fakes came to be part of its collection, noting, “Tracing the story is not proving easy.”
“The diamond has been in the museum’s collection since the 1960s and the sapphire since the 1970s. The person in charge of the collection back then is already dead, and although the gems were kept under lock and key from the start, it will be hard to ascertain what happened,” Stehlík said. “The collection of five thousand precious stones and minerals was located at different sites and was moved on more than one occasion.”
He added the museum would now “thoroughly” audit the entirety of its artefacts over the next three years. However, he noted there was a “bright side” to the incident.
“When you have a collection of 20 million artefacts, then a certain fraction of that may prove to be problematic. These things happen,” Stehlík said. “So we will push ahead with the audit and I think we may even organise an exhibition of fakes in this and other world museums when it is concluded in 2020.”
Founded in 1818, the National Museum of Prague exhibits scientific and historical collections.
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