Paleolithic (beginning с 2.5 million years ago) characterized by crudely worked pebble tools.
Oldowan tools, made of quartz, quartzite, or basalt, are chipped in two directions to form simple, rough implements for chopping, scraping, or cutting. The industry is associated with early hominids, such as {{link=Homo habilis">Homo habilis and possibly also Australopithecus robustus , and has been found at Olduvai Gorge (from which its name derives), Lake Turkana (see Lake Turkana remains ), and the Afar region of Ethiopia. Oldowan tools were made for nearly 1.5 million years before the emergence of the Acheulean industry .