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With the very little Spanish that I know and some dictionaries and textbooks, I have been doing the best I can to read the article by Lechtman (1997) about the bronzes of the Horizonte Medio of the South American Andes. One of the things that I noted was a grouping of bronze artifacts at Tiwanaku and Lukurmata consisting of a copper-arsenic-nickel alloy. The nickel content of this alloy ranges from about 1.4 to 3.6 percent. Looking at other papers that give detailed analyses of Andean copper ores, I find that the nickel in different ores is typically not detectable and at most around 70 to 300 ppm. Other analyses give nickel content for copper ores as ranging from 0.002 to 0.006 percent nickel. These low figures suggest that the nickel isn't being concentrated from the ores. I haven't found anything in either the smelting process, e.g. Lechtman and Klein (1999), or would be added that would account for the "high" nickel content of the Cu-As-Ni alloy. What could have been the source of the nickel in this Cu-As-Ni alloy? References Lechtman, H., 1997, El bronze arsenical y el Horizonte Medio. in Varon Gabai, R., and Flores Espinoza, J., eds., pp. 153-186, Arqueologia, Antropologia e Historia en los Andes: Homenaje a Maria Rostworowski. Instituto de Estudios Peruanos, Lima Peru. Lechtman, H., and Klein, S., 1999, The production of copper-arsenic alloys (arsenic bronze) by cosmelting: modern experiment, ancient practice. Journal of Archaeological Science. vol. 26, no. 5, pp. 497-526. NOTE: I am still waiting on interlibrary loan for Lechtman's 1998 article in "Metallurgica Antiqua." Yours, Paul Paul V. Heinrich LGS-LSU P.O. Box G University Station Baton Rouge, LA 70893-4107 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%