Lithic reduction

Lithic reduction is the shaping of stone by detaching flakes to make tools, sharpen edges, or produce usable flakes. The resulting marks and debris preserve evidence of how stone was worked.

Conchoidal fracture: A curved fracture that spreads through brittle materials such as flint, producing shell-like surfaces. It explains how a controlled blow can detach a sharp stone flake.
Flint: A hard, fine-grained sedimentary rock that fractures conchoidally and can form sharp edges. Its predictable fracture made it a widely used material for knapping.
Biface: A stone artifact shaped by removing flakes from both faces. Bifaces are made through sustained reduction on two surfaces.
Oldowan: An early stone-tool industry characterized by simple cores and flakes, known from sites dating to about 2.6 million years ago. Oldowan assemblages provide some of the earliest evidence of systematic stone reduction.
Clovis point: A fluted stone projectile point associated with Clovis archaeological sites in North America. Its channel flake illustrates a distinctive final stage of tool shaping.
Hard-hammer percussion: A knapping technique that detaches flakes by striking stone with a hard stone hammer. Direct impacts from stone hammers are a basic way to initiate flake removal.
Chert: A fine-grained sedimentary rock composed mainly of microcrystalline silica. Chert’s fracture properties make it suitable for producing sharp flakes.
Hand axe: A large, usually bifacial stone tool with a pointed or rounded working end. Its shape results from extensive flake removal across both faces.
Acheulean: A stone-tool industry known especially for bifacial hand axes and cleavers, beginning roughly 1.76 million years ago. Acheulean tools show increasingly organized bifacial reduction.
Ötzi's tools: The preserved tools and equipment found with Ötzi, a Copper Age individual discovered in the Alps. His chert tools preserve edges and wear from late prehistoric stoneworking.

Linked from 16 pages