Bulb Of Percussion
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Bulb Of Percussion
In lithic analysis, a subdivision of archaeology, a bulb of applied force (also known as a bulb of percussion or simply bulb of force) is a defining characteristic of a lithic flake. Bulb of applied force was first correctly described by Sir John Evans, the cofounder of prehistoric archeology. However, bulb of percussion was coined scientifically by W.J. Sollas. When a flake is detached from its parent core, a portion of the Hertzian cone of force caused by the detachment blow is detached with it, leaving a distinctive bulb on the flake and a corresponding flake scar on the core. In the case of a unidirectional core, the bulb of applied force is produced by an initiated crack formed at the point of contact, which begins producing the Hertzian cone. The outward pressure increases causing the crack to curve away from the core and the bulb formation. The bulb of applied force forms below the striking platform as a slight bulge. If the flake is completely crushed the bulb will not be vis ...
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Lithic 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 various physical attributes, and examining other visible features (such as noting the presence or absence of cortex, for example). The term 'lithic analysis' can technically refer to the study of any anthropogenic (human-created) stone, but in its usual sense it is applied to archaeological material that was produced through lithic reduction (knapping) or ground stone. A thorough understanding of the lithic reduction and ground stone processes, in combination with the use of statistics, can allow the analyst to draw conclusions concerning the type of lithic manufacturing techniques used at a prehistoric archaeological site. For example, they can make certain equation between each the factors of flake to predict original shape. These data ...
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Archaeology
Archaeology or archeology is the scientific study of human activity through the recovery and analysis of material culture. The archaeological record consists of artifacts, architecture, biofacts or ecofacts, sites, and cultural landscapes. Archaeology can be considered both a social science and a branch of the humanities. It is usually considered an independent academic discipline, but may also be classified as part of anthropology (in North America – the four-field approach), history or geography. Archaeologists study human prehistory and history, from the development of the first stone tools at Lomekwi in East Africa 3.3 million years ago up until recent decades. Archaeology is distinct from palaeontology, which is the study of fossil remains. Archaeology is particularly important for learning about prehistoric societies, for which, by definition, there are no written records. Prehistory includes over 99% of the human past, from the Paleolithic until the adven ...
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Lithic Flake
In archaeology, a lithic flake is a "portion of rock removed from an objective piece by percussion or pressure,"Andrefsky, W. (2005) ''Lithics: Macroscopic Approaches to Analysis''. 2d Ed. Cambridge, Cambridge University Press and may also be referred to as simply a ''flake'', or collectively as debitage. The objective piece, or the rock being reduced by the removal of flakes, is known as a core.Andrefsky, W. (2005) ''Lithics: Macroscopic Approaches to Analysis''. 2d Ed. Cambridge, Cambridge University Press Once the proper tool stone has been selected, a percussor or pressure flaker (e.g., an antler tine) is used to direct a sharp blow, or apply sufficient force, respectively, to the surface of the stone, often on the edge of the piece. The energy of this blow propagates through the material, often ( but not always) producing a Hertzian cone of force which causes the rock to fracture in a controllable fashion. Since cores are often struck on an edge with a suitable angle (<90°) ...
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Lithic Core
In archaeology, a lithic core is a distinctive artifact that results from the practice of lithic reduction. In this sense, a core is the scarred nucleus resulting from the detachment of one or more flakes from a lump of source material or tool stone, usually by using a hard hammer precursor such as a hammerstone. The core is marked with the positive scars of these flakes. The surface area of the core which received the blows necessary for detaching the flakes is referred to as the striking platform. The core may be discarded or shaped further into a core tool, such as can be seen in some types of handaxe. The purpose of core reduction may be to rough out a blank for later refinement into a projectile point, knife, or other stone tool, or it may be performed in order to obtain sharp flakes, from which a variety of simple tools can be made. Generally, the presence of a core is indicative of the latter process, since the former process usually leaves no core. Because the morpholo ...
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Hertzian Cone
A Hertzian cone is the cone produced when an object passes through a solid, such as a bullet through glass. More technically, it is a cone of force that propagates through a brittle, amorphous, or cryptocrystalline solid material from a point of impact. This force eventually removes a full or partial cone in the material. This is the physical principle that explains the form and characteristics of the flakes removed from a core of tool stone during the process of lithic reduction. This phenomenon is named after the German physicist Heinrich Rudolf Hertz, who first described this type of wave-front propagation through various media. Although it might not be agreed by all, natural phenomena which have been grouped with the Hertzian cone phenomena include the crescentic " chatter marks" made on smoothed bedrock by glacial ice dragging along boulders at its base, the numerous crescentic impact marks sometimes seen on pebbles and cobbles, and the shatter cones found at bolide impac ...
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Proximal End
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatomy ...
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Knapping
Knapping is the shaping of flint, chert, obsidian, or other conchoidal fracturing stone through the process of lithic reduction to manufacture stone tools, strikers for flintlock firearms, or to produce flat-faced stones for building or facing walls, and flushwork decoration. The original Germanic term ''knopp'' meant to strike, shape, or work, so it could theoretically have referred equally well to making statues or dice. Modern usage is more specific, referring almost exclusively to the hand-tool pressure-flaking process pictured. It is distinguished from the more general verb "chip" (to break up into small pieces, or unintentionally break off a piece of something) and is different from "carve" (removing only part of a face), and "cleave" (breaking along a natural plane). Method Flintknapping or knapping is done in a variety of ways depending on the purpose of the final product. For stone tools and flintlock strikers, chert is worked using a fabricator such as a hammersto ...
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Arrowhead
An arrowhead or point is the usually sharpened and hardened tip of an arrow, which contributes a majority of the projectile mass and is responsible for impacting and penetrating a target, as well as to fulfill some special purposes such as signaling. The earliest arrowheads were made of stone and of organic materials; as human civilizations progressed, other alloy materials were used. Arrowheads are important archaeological artifacts; they are a subclass of projectile points. Modern enthusiasts still "produce over one million brand-new spear and arrow points per year". A craftman who manufactures arrowheads is called an arrowsmith.Paterson ''Encyclopaedia of Archery'' p. 20 History In the Stone Age, people used sharpened bone, flintknapped stones, flakes, and chips and bits of rock as weapons and tools. Such items remained in use throughout human civilization, with new materials used as time passed. As archaeological artifacts such objects are classed as projectile p ...
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Flint
Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Flint was widely used historically to make stone tools and start fires. It occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones.''The Flints from Portsdown Hill''
Inside the nodule, flint is usually dark grey, black, green, white or brown in colour, and often has a glassy or waxy appearance. A thin layer on the outside of the nodules is usually different in colour, typically white and rough in texture. The nodules can often be found along s and

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Knapping
Knapping is the shaping of flint, chert, obsidian, or other conchoidal fracturing stone through the process of lithic reduction to manufacture stone tools, strikers for flintlock firearms, or to produce flat-faced stones for building or facing walls, and flushwork decoration. The original Germanic term ''knopp'' meant to strike, shape, or work, so it could theoretically have referred equally well to making statues or dice. Modern usage is more specific, referring almost exclusively to the hand-tool pressure-flaking process pictured. It is distinguished from the more general verb "chip" (to break up into small pieces, or unintentionally break off a piece of something) and is different from "carve" (removing only part of a face), and "cleave" (breaking along a natural plane). Method Flintknapping or knapping is done in a variety of ways depending on the purpose of the final product. For stone tools and flintlock strikers, chert is worked using a fabricator such as a hammersto ...
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