We're analyzing a 17th-18th-century collection form a New Englnad site. We're wondering if anyone knows the formula for determining penny wieght for this period? Also, Nelson and Noel Hume do not have categories for tacks other than furniture tacks during this period. Does anyone know of any references that deal with handwrought tacks vs. sprigs vs. brads vs. nails in the colonial period? Thanks, Rita Reinke Claire Carlson UMass Archaeological Services