Underwater mosaic excavation

During a rescue excavation at the centre of Thessaloniki, a Roman
floor mosaic was discovered 6 meters below the street level. One
fourth of the original floor is preserved and consists of a central
panel with a dancing female figure, surrounded by smaller panels end
geometric designs. Its condition is good but unfortunately its
surface is approximately 40 cm below the water level. Although the
plot is not far from the sea the water is not saline. A few springs
seem to exist at the surface level.

Blocklifting with the traditional method, seems impossible. Could
anybody suggest any innovative methods for the whole or even the
central panel of the mosaic?

Maria Mavrommati
Restorator
Archaeology Museum of Thessaloniki
Greece

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                  Conservation DistList Instance 9:60
                   Distributed: Monday, March 4, 1996
                        Message Id: cdl-9-60-003
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