> Hi,
>
> I read Kathy Ehrhardt's e-mail regarding copper wires with 'B' and 'e'
> profiles from native American sites in Missouri with great interest. I
> have encountered several examples of 'e' profile "wires" in pre-colonial
> Andean metal objects (Heather Lechtman has also reported such finds).
> Specifically, shafts of needles and pins (2-4 mm in diameter) were often
> made by 'rolling' a thin sheet and then hammering it to produce a circular
> cross section. The composition of the pieces is copper with arsenic
> content varying between 0.5 % and 4 %. All the examples I have examined
> come from well-dated pre-colonial contexts and therefore are of native
> manufacture. The needle and pin shafts are wonderfully consistent in
> diameter, very straight, well finished. It was clearly within the
> capabilities of Andean metal workers to produce copper and copper-alloy
> wire-like pieces by rolling or folding a thin sheet about its longer axis.
> The length of some needles does approach 10 cm.
>
> A comparison of the composition of 'rolled' shafts vs. ones that appear
> to have been hammered from thin cast pieces with roughly rectangular cross
> sections did not find significant correlation between the method of
> manufacture and arsenic content.
>
> Best wishes,
> Aniko Bezur
> ---------------------------
> Aniko Bezur
> Buffalo State College
> Art Conservation Department, RH 230
> 1300 Elmwood Avenue
> Buffalo, NY 14222
>
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