As obsidian moved farther from its source, the size of the pieces traded progressively decreased and the relative value increased. ...Small blades were obtained simply by smashing a large block with a stone, while in time blades were broken into smaller fragments to obtain newly sharp edges (Harding 1967: 42).

Establishing consistent links between the types of social structure and the forms and organization of production in association with exchange was the approach taken by Ericson (1982) and, most explicitly, by Torrence (1986). By investigating the standardization and error rates in blade reduction strategies at obsidian production sites on the Greek island of Melos, Torrence was able to evaluate the degree of specialization involved in the quarrying and production of obsidian at the source.

In her review of archaeological site-oriented studies of exchange, Torrence (1986: 27-37) uses a few major themes to characterize site-oriented investigations. These themes include measures of abundance, source composition percentages, and the variability in archaeological context and artifactual form of import.