Ken is right in stating that Hong et al show massive levels of global
pollution by lead in late Greek and Roman times. The full references are:
Hong, S., Candelone, J.-P., Patterson, C.C. and Boutron, C.F. (1994).
Greenland ice evidence of hemispheric lead pollution two millennia ago by
Greek and Roman civilizations. Science 265:1841-1843.
Hong, S., Candelone, J.-P., Patterson, C.C. and Boutron, C.F. (1996).
History of ancient copper smelting pollution during Roman and Medieval
times recorded in Greenland ice. Science 272:246-248.
Lead levels jump to four times the previous level in greenland ice during
Greek and Roman times. With the collapse of the Western Roman empire ca.
600 AD the levels drop sharply, and do not attain the Roman levels again
for another thousand years.
Ken is wrong however in assuming that this is a reflection of lead
smelting; it is very clearly a consequence of the technology used by
Greeks and Roman for producing silver - i.e. cupellation. As anyione who
has tried to do it will realize, the oxidation of the molten lead during
cupellation produces a lot of white fumes. These are lead oxide, and it
was in this form that lead was carried into the trophosphere and thence
north to Geenland on the jet stream.
P.S. I enjoyed Ken's typo - lewd smelting, indeed!
----------------------
David J Killick
Associate Professor, Department of Anthropology
University of Arizona, Tucson, AZ 85721-0030
Phone (520)621-8685; FAX 621-2088
[log in to unmask]
http://www.mse.arizona.edu/faculty/killick.html
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