In archaeology Archaeology, archeology, or archæology is the science that studies human cultures through the recovery, documentation, analysis, and interpretation of material remains and environmental data, including architecture, artifacts, features, biofacts, and landscapes. Because archaeology's aim is to understand humankind, it is a humanistic endeavor, a lithic flake is a "portion of rock In geology, rock is a naturally occurring solid aggregate of minerals and/or mineraloids removed from an objective piece by percussion or pressure,"[1] and may also be referred to as a chip Chip Time, is the time a runner passes the from the starting to the finishing lines in a race. It is recorded by a chip that records when these points are passed by the runner. In such races as a marathon the race can start long before the runners at the back of the field pass the starting point, and begin what would be the main course of the race or spall Spall are flakes of a material that are broken off a larger solid body and can be produced by a variety of mechanisms, including as a result of projectile impact, corrosion, weathering, cavitation, or excessive rolling pressure . Spalling and spallation both describe the process of surface failure in which spall is shed, or collectively as debitage. The objective piece, or the rock being reduced by the removal of flakes, is known as a 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 percussor such as a hammerstone. The core is marked with the.[2] Once the proper tool stone A stone tool is, in the most general sense, any tool made partially, or entirely out of stone. Although stone-tool-dependent cultures exist even today, most stone tools are associated with prehistoric societies that no longer exist has been selected, a percussor or pressure flaker (e.g. an antler Antlers are the usually large and complex bony appendages of most deer species, mostly worn by males; only female caribou and reindeer have antlers, though these are normally smaller than those of the males. Each antler grows from an attachment point on the skull called a pedicle. While an antler is growing it is covered with highly vascular skin 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 A Hertzian cone is the cone of force that propagates through a brittle, amorphous or cryptocrystalline solid material from a point of impact, eventually removing a full or partial cone. An example often occurs when a plate-glass window is struck by a small object, such as an airgun projectile. This is the physical principle that explains the form of force which causes the rock to fracture in a controllable fashion. Since cores are often struck on an edge with a suitable angle (x<90°) for flake propagation, the result is that only a portion of the Hertzian cone is created. The process continues as the flintknapper Knapping is the shaping of flint, chert, obsidian or other 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 detaches the desired number of flakes from the core, which is marked with the negative scars of these removals. The surface area of the core which received the blows necessary for detaching the flakes is referred to as the striking platform.
Flakes may be produced by a variety of means. Force may be introduced by direct percussion (striking the core with a percussor such as a rock or antler), indirect percussion (striking the core with an object, sometimes referred to as a "punch," which itself is struck by a percussor, similar to the use of a hammer and chisel to shape stone), or by pressure. Additionally, flakes may be initiated in a Hertzian, bending, or wedging fashion. When a flake is detached from its core in a Hertzian fashion, the flake propagates in a conchoidal manner from the point of impact or pressure, producing a (usually) partial Hertzian cone. The cone of force often leaves a distinctive bulb of applied force on the flake and a corresponding flake scar on the core. A bending initiation results when a flake initiates not at the point where the force was applied, but rather further away from the edge of the core, resulting in a flake with no Hertzian cone or bulb of applied force and few if any of the characteristics ripples or undulations seen on the ventral surface of conchoidally produced flakes. Wedging initiation is the result of a strong hammer blow. At impact, concenctric radii emanate from the point of percussion, but unlike conchoidal fracture, the force travels along what would be the center of the Hertzian cone. The bipolar reduction technique is typified by its use of wedge initiation. Like bending initiation, no bulb of applied force results from wedging initiation, although in the bipolar technique, flakes may appear to have two points of percussion, on opposite ends, due to the fact that the core has been fractured by a hammer and anvil technique. The core is placed on a hard surface or "anvil" and is struck above by a hammer, thus the fracture may propagate from both ends simultaneously.
The end which received the blow or pressure is referred to as the proximal end of the flake; the terminal end is referred to as the distal end. The side displaying the bulb of force but without flake scars (barring an errailure flake scar or additional working of the flake) is called the ventral (or interior) surface, while the opposite side, displaying the flake scars of previous removals, or the cortical or original rock surface, is the dorsal (or exterior) surface.
On most natural cobbles or nodules of source material, a weathered outer rind called a cortex covers the unweathered inner material. Flakes are often differentiated by the amount of cortex present on their dorsal surfaces, because the amount of cortex indicates when in the sequence of reduction the flake came from. Primary flakes are those whose dorsal surfaces are entirely covered with cortex; secondary flakes have at least a trace of cortex on the dorsal surface; and tertiary (interior) flakes lack cortex, having derived entirely from the interior of the core. Primary flakes and secondary flakes are usually associated with the initial stages of lithic reduction Lithic reduction involves the use of a hard hammer precursor, such as a hammerstone, a soft hammer fabricator , or a wood or antler punch to detach lithic flakes from a lump of tool stone called a lithic core (also known as the "objective piece"). As flakes are detached in sequence, the original mass of stone is reduced; hence the term, while tertiary flakes are more likely to be associated with retouching and bifacial reduction activities.
Prominent bulbs of force generally indicate that a hard hammer percussor (hammerstone In archaeology, a hammerstone is a hard cobble used to strike lithic flakes off a lump of tool stone during the process of lithic reduction. Often, a hammerstone is made of a material such as limestone or quartzite, is often ovoid in shape , and develops telltale battering marks on one or both ends. Hammerstones are often found in archaeological) was used to detach the flake; flakes displaying this characteristic are referred to as conchoidal flakes. Hard hammer flakes are indicative of primary reduction strategies (e.g., core reduction, roughing of blanks and preforms, and the like). More moderate and diffuse bulbs may indicate the use of a soft hammer percussor -- such as bone Bones are rigid organs that form part of the endoskeleton of vertebrates. They function to move, support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue. Because bones come in a variety of shapes and have a complex internal and external structure, wood Wood is an organic material; in the strict sense it is produced as secondary xylem in the stems of trees . In a living tree it transfers water and nutrients to the leaves and other growing tissues, and has a support function, enabling woody plants to reach large sizes or to stand up for themselves. However, wood may also refer to other plant, or antler Antlers are the usually large and complex bony appendages of most deer species, mostly worn by males; only female caribou and reindeer have antlers, though these are normally smaller than those of the males. Each antler grows from an attachment point on the skull called a pedicle. While an antler is growing it is covered with highly vascular skin -- which produces the bending flakes often associated with bifacial thinning and trimming. The relative abundance of each type of flake can indicate what sort of lithic work was going on at a particular spot at a particular point in time.
A blade is defined as a flake with parallel or subparallel margins that is usually at least twice as long as it is wide[3]. There are numerous specialized types of blade flakes. Channel flakes are characteristic flakes caused by the fluting of certain Paleo-Indian Paleoindians or Paleoamericans were the first peoples to enter and inhabit the American continent during the final glacial episodes of the late Pleistocene. The prefix "paleo" comes from the Greek adjective palaios meaning "old." The term Paleoindian applies to a specific archaeological period in the Western Hemisphere and is projectile points In archaeology, a projectile point is an object that was hafted and used either as knife or projectile tip or both, commonly called an arrowhead. Occasionally, projectile points made of worked bone or ivory are found at archaeological sites, but generally the term is reserved for a refined chipped-stone biface. Projectile points fall into two; such fluting produced grooves in the projectile points which may have facilitated hafting. Prismatic blades In archaeology, a prismatic blade is a long, narrow, specialized lithic flake with parallel margins. Prismatic blades are removed from polyhedral blade cores through pressure reduction. This process results in a very standardized finished tool and waste assemblage. While the prismatic blade industry is most often associated with obsidian , it is are long, narrow specialized blades with parallel margins which may be removed from polyhedral blade cores, another common lithic feature of Paleo-Indian lithic culture. Prismatic blades are often triangular in cross section with several facets or flake scars on the dorsal surface.
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