Colin Thomas is a 7th year graduate student in Archaeology at Yale specializing in archaeometallurgy. As part of his doctoral research, he has been studying the Chimu Era (900A.D. – 1470 A.D.) copper smelting site of Dos Cruces, located near the modern town of Oyotùn on the North Coast of Peru. Dos Cruces is the first smelting site excavated from this time period in the New World and Colin’s field work has uncovered smelting-related features as well as a variety of indicators of ritual activity. His dissertation focuses on understanding both the technical aspects of smelting at Dos Cruces and the ways that people living there used and understood that technology. Colin has been working in the Technical Studies Lab of IPCH to document 30 samples from the site, ranging from small bits of slag to fabric wrapped crucibles. He prepared polished cross sections that he examined with reflected-light (darkfield) optical microscopy as well as scanning electron microscopy coupled with energy-dispersive x-ray spectroscopy. Colin received a Doctoral Dissertation Improvement Grant from the National Science Foundation’s Archaeology program to support his research.