Abstract
Production of marine shell beads in island and coastal settings was an important activity in prehistory, with important political and economic ties. Currently, there are few methods to track beads to their locus of production. Examining the spatial distribution of bead types provides one method of doing so. Chemical and stable isotopic methods provide an additional and independent means of testing hypotheses generated by spatial distributions. We use stable oxygen, carbon, and strontium isotope data to reconstruct provenance zones for 18 Olivella biplicata beads from the Los Angeles Basin and San Nicolas Island, California. We compare the results to isotopic data from modern and radiocarbon-dated whole shells collected along the Pacific Coast. Results indicate that all 18 beads were manufactured from shells growing in open coast locations south of Point Conception. Differences in isotopic composition between bead types suggest that not all were produced in the same location. Some, such as callus beads (K1), have highly variable composition, suggesting production in a range of locations. Others, such as thin lipped (E1), seem to have been produced in more restricted regions.