The Onondaga Escarpment contains significant outcrops of flint (a type of chert) which bears the escarpment's name. This variety of chert was of great importance to First Nations peoples throughout Southern Ontario, who used it to make stone tools (lithics) such as projectile points and hide scrapers. This variety of chert, which is of reasonably high-quality and which was highly valued by First Nations peoples, is often a common variety of chert recovered archaeologically from sites relatively adjacent to outcrops; for example, Onondaga-variety chert comprises 95% of all of the flint material from some sites in Milton, Ontario. The material has also been found as well at some distance from its original source; Onondaga chert has been recovered at the late archaic Duck Lake archaeological site in northern Michigan, circa 400 kilometers from the nearest outcropping of the material. This wide distribution implies either a very large seasonal migration of ancient peoples or long-distance trade routes, with both likely being the case at different times throughout the prehistory of the Great Lakes region.