FABLES about the origins of some of the world's most prized gemstones are being put to the test by geochemists in France and Colombia. By analysing oxygen levels in famous emeralds they have proved that some of the gems did indeed come from forgotten mines in Asia.
Half of all emeralds hail from mines discovered 400 years ago in Colombia by the Spanish. The only established sources of emeralds before then were in Egypt and Austria. But the origins of so-called "old mine" emeralds sold by Indian traders in the 16th century have been a mystery.
Experts suspected that the gems came from old mines in Asia, but there has never been any proof. "It's a fable of the mining road, that the cut emeralds of India came from old mines that were forgotten," says Gaston Giuliani of the French government's Centre for Petrography and Geochemistry in Nancy.
The researchers ...
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