The conservation and analysis of some ancient copper alloy beads from Colombia

Abstract

The conservation of a corroded copper lump revealed the presence of 10 necklace beads still threaded on the original string. The conservation treatment is described. The beads, from the District of Nariño, Colombia, were analyzed using X-ray fluorescence, atomic absorption spectrophotometry, and electron probe microanalysis. The results of the analysis showed the beads to have been made of an arsenical copper and, in one case, a tin bronze, an alloy not previously reported from ancient Colombia. The results of the analyses are discussed.