Charles Reher has a good summary article on the Spanish Diggings
quarries in the volume "Raw Material Economies Among Prehistoric
Hunter-Gatherers", edited by Anta Montet-White and Steve Holen,
University of Kansas Publications in Anthropology 19, 1991 - James
James Wettstaed [log in to unmask]
Shared Service Archaeologist, Mark Twain National Forest
"all opinions expressed are my own etc."