Evidence for changes in human mobility is fundamental to interpretations of transitions in human socioeconomic organization. Showing changes in mobility requires both archaeological proxies that are sensitive to movement and a clear understanding of how different mobility configurations influence their patterning. This study uses computer simulation to explore how different combinations of reduction, selection, transport, and discard of stone artifacts generate patterning in the cortex ratio, a geometric proxy used to demonstrate movement at the assemblage level. A case study from western New South Wales, Australia, shows how cortex ratios are used to make inferences about movement. Results of the exploratory simulation show that redundancy in movement between discards reduces variability in cortex ratios, while mean assemblage values can be attributed to the relative proportions of artifacts carried into and out of the assemblages. These results suggest that raw material availability is a potentially crucial factor in determining what kinds of mobility are visible in assemblages, whereby different access to raw material can shift the balance of import and export of stone in an otherwise undirected movement configuration. These findings are used to contextualize distributions of cortex ratios from the raw material-rich study area, prompting suggestions for further fieldwork.