Raw material impact strength and flaked stone projectile point performance

Archaeologists have previously proposed several different measures of flaked stone raw material “quality”, but this variable has proven difficult to quantify, and the precise characteristics that improve performance remain unclear. This paper presents the results of controlled experiments that were designed to test projectile points made from stones with varying impact strength. By comparing an independent measure of strength with projectile point experimental data, our research suggests that this variable can be objectively measured, and it is a good predictor of some aspects of projectile tip function. Our results show that highly homogenous fine-grained materials with low impact strength (e.g., obsidian) perform well when penetrating elastic materials such as skin and muscle. These same materials, however, function poorly when penetrating more inelastic materials like rawhide, and they are substantially less durable.