tool material
121metalwork — metalworker, n. /met l werrk /, n. objects made of metal. [1840 50; METAL + WORK] * * * Useful and decorative objects fashioned of various metals. The oldest technique is hammering. After с 2500 BC, casting was also used, molten metal being… …
122DNA — For a non technical introduction to the topic, see Introduction to genetics. For other uses, see DNA (disambiguation). The structure of the DNA double helix. The atoms in the structure are colour coded by element and the detailed structure of two …
123Genetics — This article is about the general scientific term. For the scientific journal, see Genetics (journal). Part of a series on Genetics Key components Chromosome DNA • RNA Genome …
124Lithic reduction — The Levallois technique of flint knapping Lithic reduction involves the use of a hard hammer precursor, such as a hammerstone, a soft hammer fabricator (made of wood, bone or antler), or a wood or antler punch to detach lithic flakes from a lump… …
125Lithic analysis — In archaeology, lithic analysis is the analysis of stone tools and other chipped stone artifacts using basic scientific techniques. At its most basic level, lithic analyses involve an analysis of the artifact’s morphology, the measurement of… …
126Drill — For other uses, see Drill (disambiguation). Drill scheme A drill or drill motor is a tool fitted with a cutting tool attachment or driving tool attachment, usually a drill bit or driver bit, used for drilling holes in various materials or… …
127Burnishing (metalworking) — Burnishing is the plastic deformation of a surface due to sliding contact with another object. Visually, burnishing smears the texture of a rough surface and makes it shinier. Burnishing may occur on any sliding surface if the contact stress… …
128Stone Age — the period in the history of humankind, preceding the Bronze Age and the Iron Age, and marked by the use of stone implements and weapons: subdivided into the Paleolithic, Mesolithic, and Neolithic periods. [1860 65] * * * First known period of… …
