[Aztlan] Gold extraction in the ancient Andes

[michael ruggeri]

Listeros,

A team of geologists and archaeologists have found that ancient pre- 
Inca cultures may have known how to refine gold with mercury  
amalgamation. This is still used today to distill almost pure gold and  
silver from ore. The Romans did this but the technique was not used in  
Europe till the 12th century. The team analyzed residual mercury  
levels in 7 samples from Peru and Columbia. 3 of the samples were from  
the Sican culture (750-1375 CE). They found signs of amalgamation  
similar to the technique used today in gold foil. The report on this  
finding was given at the Geological Society of America's annual meeting.

There is some criticism of the findings. Almost all Sican gold was  
looted, so the context of this gold is uncertain. Izumi Shimada, head  
of the Sican Archaeological Project, said that the cinnabar used to  
cover the dead elite contains a lot of mercury-sulfur which could have  
contaminated the samples. The team replied that they did carefully  
remove the cinnabar and the tests revealed consistent measurements and  
not random variations between samples which would have been the case  
if there had been contamination.

Science Now has the story here;
http://sciencenow.sciencemag.org/cgi/content/full/2009/1020/2

A tiny URL;
  http://tiny.cc/nddXy

Mike Ruggeri

Mike Ruggeri's Andean Archaeology News and Links
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