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Roman emerald mining in the Egyptian Eastern DesertBy, J. Bubury We have studied three groups of emerald mines in the Eastern Desert of Egypt and collected from the mines, fragments of discarded and inferior emerald material for petrological characterisation. The mines show evidence of use from about 300 BS to 1500 AD. Although documentary evidence suggests that the mines operated from earlier dates no evidence to confirm this was discovered. Emeralds were much used in jewellery since Roman and Hellenistic times but the Egyptian mines were abandoned after the discovery of the New World and the abundant emeralds of Columbia. Our study which includes geological, architectural and archaeological evidence from the sites was conducted in 1994. From pottery sherds examined in situ we were able to group sites by age. They were:
The geological setting of the emeralds is at the contact between schists and granite pegmatites or quartz lenses associated with granite pegmatites. The green colour of the emeralds if thought to arise from reduced iron oxide provided by the schists. Optical microscopy showed that the fragments recovered from the mines consisted of zoned and polycrystalline beryl. Electron microprobe analysis showed that there was considerable variation in the major element composition within grains. Furthermore this inherent variation eclipsed the variation between Egyptian and other emeralds with the exception of emeralds from Columbia and the Urals. |