The question of the isolation of producers and traders from consumers also connects theories about exchange with the issue of the physical form of the exchange goods. Archaeologists investigating the role of stone artifacts in prehistoric economies observe that lithic manufacture is a subtractive technology as stone artifacts always get smaller with use and maintenance. The degree of reduction of stone material at a lithic source determines the kinds of forms that subsequent artifacts will take.

Jonathon Ericson (1984) applies Sahlins' concept of a continuum of social distance in exchange relationships, discussed above, to the directional, reductive nature of lithic production systems. He explores the idea that the degree of lithic reduction that may occur could be reduced when social distance increases because the producer would have less information about the consumer and the end forms that material will take (Ericson 1984: 6). For example, if the procurer does not know if the nodule will be formed into bifacial lancoleate knife or a triangular projectile point by the consumer, it would be better to leave the nodule in a larger form.

Exchange partners can be slow to respond to changes in the needs of consumers in a given exchange system (Ericson 1984: 6;Harding 1967;Rappaport 1967;Spence 1982), and the effects of social distance can impact production, exchange, or consumption patterns. The implications of social distance for lithic reduction are that, as a subtractive process, reduction circumscribes the potential artifact forms that a nodule of raw material may take in the future. Countering this tendency, people can reduce risk in tool production by producing blanks closer to the source of a raw material where the value of a material is lessened and the costliness of knapping error or breakage, and inconsistent or poor-quality material, is reduced. Stylistically, producers may wish to impart a local motif to the material; alternately, in order to maximize distributive potential, a good may be left in a minimally reduced form.