During the Middle Paleolithic period, stone-knapping techniques as well as the materials used became more diverse, with Neanderthals making tools out of stone as well as from bone. The use of bone for making tools was already established in Mousterian industry, although the fact that this material breaks down over long periods of time means that not many have survived in good condition. Denticulate tools are typical of this period, and have a denticulate edge that is made through the technique of retouching. This means that they can be used for cutting or sawing soft materials.