Minerals and Meteorites

The use of minerals and rocks by primates for making primitive tools is not confined to our species. Some chimpanzees, long-tailed macaques, and wild bearded capuchin monkeys use stone tools to crack open nuts and fruits, and in the case of coastal-dwelling macaques, shuck oysters. Hominins were using stone tools to scrape flesh from ungulate carcasses 3.4 million years ago. By 1.6 million years ago, hominins had discovered that some rocks (e.g., flint, chert, rhyolite, quartzite) were more suitable than others (e.g., limestone, sandstone, shale) for making hand axes; they presumably developed crude criteria (e.g., color, heft, friability, location) for distinguishing them.