Lithic flake

In archaeology, a lithic flake is a "portion of rock removed from an objective piece by percussion or pressure,"[1]:255 and may also be referred to as a chip or spall, or collectively as debitage. The objective piece, or the rock being reduced by the removal of flakes, is known as a core.[1]:254, 258 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 (x<90°) for flake propagation, the result is that only a portion of the Hertzian cone is created. The process continues as the flintknapper 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.

Lithic flake
Fundamental elements for the technic description of a lithic flake

Production

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, usually producing a 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, concentric 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, because 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, 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) 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, wood, or antler—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.

Lithic blade and core
Prismatic blade and its core that made with prismatic reduction technology. The blade flake that marks with A can fit to where A' marks on this core.

A blade is defined as a flake with parallel or subparallel margins that is usually at least twice as long as it is wide.[1]:253 There are numerous specialized types of blade flakes. Channel flakes are characteristic flakes caused by the fluting of certain Paleo-Indian projectile points; such fluting produced grooves in the projectile points which may have facilitated hafting. Prismatic blades 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. Prismatic blades begin to appear in high frequencies during the transition between the Middle and Upper Paleolithic.This lithic technology basically replaces the Levallois reduction technology.

Other flake characteristics

The striking platform is the point on the proximal portion of the flake on which the detachment blow fell or pressure was placed. This may be natural or prepared. Termination type is a characteristic indicating the manner in which the distal end of a flake detached from a core. Flake terminations may be feathered, hinged, stepped, or plunging (also known as overshot or outrepassé). Feathered terminations are often very sharp, as the flake gradually reduces to a very fine thickness before the force exits the core and removes the flake. Hinged terminations are the result of the force rolling away from the core, resulting in a rounded distal end. Step terminations result when a flake prematurely breaks or snaps during removal, leaving a distal end that is often squared off. Plunging flakes are the result of the force rolling back towards the core and often taking off its "bottom". Hinge, step, and plunging terminations, although sometimes deliberately formed, are usually errors called "abrupt terminations". Abrupt terminations are often indicative of internal flaws in a core or previously formed Hertzian cones on the surface.[2] Eraillures, also referred to as "bulbar scars", are tiny flake scars that appear on some bulbs of applied force. The reason they form is not entirely understood. Of those flakes that do exhibit eraillures, very few have more than one.

Secondary and tertiary flakes display dorsal flake scars, which are simply the markings left behind by flakes detached prior to the detachment of the subject flake. These flake scars are one of the lines of evidence used to infer the method of lithic reduction, or the process by which raw material is turned into useful objects.

Tools

Flakes can be modified into formal tools, which result from additional working of the piece to shape a flake into a desired form, or they can be used without further modification, and are then referred to as expedient tools. For example, scrapers, which may be made by additional removals (retouching) to the edge of a piece, or burins, which are created by a burin blow on the tip of a blade which produces a chisel-like edge which may have been used for graving and carving wood or bone. Because they require less labor to create, expedient flakes can be used strategically to provide a useful tool for a situation that does not necessarily need a formal, specialized tool (e.g., needing something sharp to cut with).[3]

References

  • Andrefsky, William, Jr. (2005) Lithics: Macroscopic approaches to analysis. 2d ed. Cambridge University Press, Cambridge.
  1. ^ a b c Andrefsky, W. (2005) Lithics: Macroscopic Approaches to Analysis. 2d Ed. Cambridge, Cambridge University Press
  2. ^ Macgregor, O.J. (2005) "Abrupt Terminations and stone artefact reduction potential". In Clarkson, C. and L. Lamb (Eds) (2005) Lithics 'Down Under': Australian Approaches to Lithic Reduction, Use and Classification. British Archaeological Reports International Monograph Series S1408. Oxford: Archaeopress
  3. ^ McCall, Grant (January 1, 2012). "Ethnoarchaeology and the Organization of Lithic Technology". Journal of Archaeological Research. 20 (2): 157–203.
Bulb of applied force

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 visible. Bulbs of applied force may be distinctive, moderate, or diffuse, depending upon the force of the blow used to detach the flake, and upon the type of material used as a fabricator. The bulb of applied force can indicate the mass or density of the tool used in the application of the force. The bulb may also be an indication of the angle of the force. This information is helpful to archaeologists in understanding and recreating the process of flintknapping. Generally, the harder the material used as a fabricator, the more distinctive the bulb of applied force. Soft hammer percussion has a low diffuse bulb while hard hammer percussion usually leaves a more distinct and noticeable bulb of applied force. Pressure flake also allowed for diffuse bulbs. The bulb of percussion of a flake or blade is convex and the core has a corresponding concave bulb. The concave bulb on the core is known as the negative bulb of percussion. Bulbs of applied force are not usually present if the flake has been struck off naturally. This allows archaeologists to identify and distinguish natural breakage from human artistry. The three main bulb types are flat or nondescript, normal, and pronounced. A flat or nondescript bulb is poorly defined and does not rise up on the ventral surface. A normal bulb on the ventral side has average height and well-defined. A pronounced bulb rises up on ventral side and is very large.When explained visually, the bulb of percussion is visible on the ventral face as opposed to the dorsal face (where it is smoother) and considered to be on the "inside" of the parent core. The bulb of percussion is the primary feature that identifies the ventral surface of a flake or blade artifact. Locating its position reveals which is the proximal end of an artifact. Along the proximal end there may be the formation of ripple marks. These ripple marks allow for the direction traveled by the applied force through the lithic when it was detached. Typically, the striking of the flake is produced by knapping (or flintknapping), a process in which requires the user to chip away material from high-silica stones like "flint" in a carefully controlled manner with special tools to produce sharp projectile points or tools. A common characteristic that is associated with the bulb of applied force is a bulbar scar. This scar is from a small chip or flake on the bulb. This is known as an eraillure flake scar. It is produced during the initial impact of flake removal. Occasionally, there is more than one contact point on a striking platform which creates a series of superimposed waves. The eraillure flake is a chip removed through contact of a dominant force wave that creates the conchoidal flake and inferior waves. Bulb of applied force is not produced by bipolar technology or wedging initiation.

Burin (lithic flake)

In the field of lithic reduction, a burin (from the French burin, meaning "cold chisel" or modern engraving burin) is a type of handheld lithic flake with a chisel-like edge which prehistoric humans used for engraving or for carving wood or bone.

Burins exhibit a feature called a "burin spall", in which toolmakers strike a small flake obliquely from the edge of the burin flake in order to form the graving edge.

Chivateros

Chivateros is an ancient stone tool quarry and associated workshop located near the mouth of the Chillón river in the Ventanilla District, northwest of Lima, Peru.

Flake tool

In archaeology, a flake tool is a type of stone tool that was used during the Stone Age that was created by striking a flake from a prepared stone core.

People during prehistoric times often preferred these flake tools as compared to other tools because these tools were often easily made, could be made to be extremely sharp & could easily be repaired. Flake tools could be sharpened by retouch to create scrapers or burins. These tools were either made by flaking off small particles of flint or by breaking off a large piece and using that as a tool itself. These tools were able to be made by this "chipping" away effect due to the natural characteristic of stone. Stone is able to break apart when struck near the edge. Flake tools are created through flint knapping, a process of producing stone tools using lithic reduction. Lithic reduction is the removal of a lithic flake from a larger stone in order to reach the desired tool shape and size. The beginning stone is called the flake lithic core. There are three steps to lithic reduction:

Hard hammer percussion is the first step. It involves knocking off the larger flakes to achieve the desired lithic core for the flake tool. In using hard hammer percussion the flake tools were made by taking metamorphic or igneous rock such as granite or quartz and striking it against the stone. This method was often used to flake large core flakes of hard rock.

Soft hammer percussion is the second step. It involves using a hammer made of bone, which was often antler, in order to knock off flakes from the lithic core. Animal antlers such as moose, deer and elk were often the most common ones used. It allows the user more control over the size and shape of the flakes knocked off. Soft hammer percussion was also used when the stone was more brittle.

Pressure flaking is the final step. It involves using a piece of bone, antler, or piece of hardwood in order to have more control of the flakes knocked off of the lithic core. One simply applies outward and downward pressure to achieve the final flake tool.

Hand axe

A hand axe (or handaxe) is a prehistoric stone tool with two faces that is the longest-used tool in human history. It is usually made from flint or chert. It is characteristic of the lower Acheulean and middle Palaeolithic (Mousterian) periods. Its technical name (biface) comes from the fact that the archetypical model is generally bifacial Lithic flake and almond-shaped (amygdaloidal). Hand axes tend to be symmetrical along their longitudinal axis and formed by pressure or percussion. The most common hand axes have a pointed end and rounded base, which gives them their characteristic shape, and both faces have been knapped to remove the natural cortex, at least partially. Hand axes are a type of the somewhat wider biface group of two-faced tools or weapons.

Hand axes were the first prehistoric tools to be recognized as such: the first published representation of a hand axe was drawn by John Frere and appeared in a British publication in 1800. Until that time, their origins were thought to be natural or supernatural. They were called thunderstones, because popular tradition held that they had fallen from the sky during storms or were formed inside the earth by a lightning strike and then appeared at the surface. They are used in some rural areas as an amulet to protect against storms.

Hand axe tools were possibly used to butcher animals; to dig for tubers, animals and water; to chop wood and remove tree bark; to throw at prey; and as a source for flake tools.

Ksar Akil flake

Ksar Akil Flake is an oval type of Lithic flake with fine, regular teeth at frequent intervals. The flint tool is named after the archaeological site of Ksar Akil in Lebanon, where several examples were found and suggested to date to the late Upper Paleolithic.Two Ksar Akil Flakes are held by the National Museum of Beirut, marked as "level V", which had a base point at around 3 metres (9.8 ft) below datum. Other examples are held by the Archaeological Museum of the American University of Beirut, Lorraine Copeland and some are also likely to be among the Ksar Akil material held in London. Five other examples are held in the Museum of Lebanese Prehistory found at Borj Barajne in the Sands of Beirut along with two worn examples discovered at Antelias cave. Another Ksar Akil flake was found at El-Emireh.

Levallois technique

The Levallois technique (IPA: [lə.va.lwa]) is a name given by archaeologists to a distinctive type of stone knapping developed by precursors to modern humans during the Palaeolithic period.

It is named after nineteenth-century finds of flint tools in the Levallois-Perret suburb of Paris, France. The technique was more sophisticated than earlier methods of lithic reduction, involving the striking of lithic flakes from a prepared lithic core. A striking platform is formed at one end and then the core's edges are trimmed by flaking off pieces around the outline of the intended lithic flake. This creates a domed shape on the side of the core, known as a tortoise core, as the various scars and rounded form are reminiscent of a tortoise's shell. When the striking platform is finally hit, a lithic flake separates from the lithic core with a distinctive plano-convex profile and with all of its edges sharpened by the earlier trimming work.

This method provides much greater control over the size and shape of the final flake which would then be employed as a scraper or knife although the technique could also be adapted to produce projectile points known as Levallois points. Scientists consider the Levallois complex to be a Mode 3 technology, as a result of its diachronic variability. This is one level superior to the Acheulean complex of the Lower Paleolithic.

Lithic

Lithic may refer to:

Relating to stone tools

Lithic analysis, the analysis of stone tools and other chipped stone artifacts

Lithic technology, the array of techniques to produce tools from stone

Lithic reduction, the process of removing flakes from a stone to make a tool

Lithic flake, the portion of a rock removed to make a tool

Lithic core, the part of a stone which has had flakes removed from it

Lithic stage, the North American prehistoric period before 10,000 years ago

Lithic fragment (geology), pieces of rock, eroded to sand size, and now sand grains in a sedimentary rock

Lithic sandstone, sandstone with a significant component of (above) lithic fragments

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 can then be used to draw an understanding of socioeconomic and cultural organization.

The term knapped is synonymous with "chipped" or "struck", but is preferred by some analysts because it signifies intentionality and process. Ground stone generally refers to any tool made by a combination of flaking, pecking, pounding, grinding, drilling, and incising, and includes things such as mortars/metates, pestles (or manos), grinding slabs, hammerstones, grooved and perforated stones, axes, etc., which appear in all human cultures in some form. Among the tool types analyzed are projectile points, bifaces, unifaces, ground stone artifacts, and lithic reduction by-products (debitage) such as flakes and cores.

Lithic reduction

In archaeology, in particular of the Stone Age, lithic reduction is the process of fashioning stones or rocks from their natural state into tools or weapons by removing some parts. It has been intensely studied and many archaeological industries are identified almost entirely by the lithic analysis of the precise style of their tools and the chaîne opératoire of the reduction techniques they used.

Normally the starting point is the selection of a piece of tool stone that has been detached by natural geological processes, and is an appropriate size and shape. In some cases solid rock or larger boulders may be quarried and broken into suitable smaller pieces, and in others the starting point may be a piece of the debitage, a flake removed from a previous operation to make a larger tool. The selected piece is called the lithic core (also known as the "objective piece"). A basic distinction is that between flaked or chipped stone, the main subject here, and ground stone objects made by grinding. Flaked stone reduction involves the use of a hard hammer percussor, 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 the lithic core. As flakes are detached in sequence, the original mass of stone is reduced; hence the term for this process. Lithic reduction may be performed in order to obtain sharp flakes, of which a variety of tools can be made, or to rough out a blank for later refinement into a projectile point, knife, or other object. Flakes of regular size that are at least twice as long as they are broad are called blades. Lithic tools produced this way may be bifacial (exhibiting flaking on both sides) or unifacial (exhibiting flaking on one side only).

Cryptocrystalline or amorphous stone such as chert, flint, obsidian, and chalcedony, as well as other fine-grained stone material, such as rhyolite, felsite, and quartzite, were used as a source material for producing stone tools. As these materials lack natural planes of separation, conchoidal fractures occur when they are struck with sufficient force; for these stones this process is called knapping. The propagation of force through the material takes the form of a Hertzian cone that originates from the point of impact and results in the separation of material from the objective piece, usually in the form of a partial cone, commonly known as a lithic flake. This process is predictable, and allows the flintknapper to control and direct the application of force so as to shape the material being worked. Controlled experiments may be performed using glass cores and consistent applied force in order to determine how varying factors affect core reduction.It has been shown that stages in the lithic reduction sequence may be misleading and that a better way to assess the data is by looking at it as a continuum. The assumptions that archaeologists sometimes make regarding the reduction sequence based on the placement of a flake into a stage can be unfounded. For example, a significant amount of cortex can be present on a flake taken off near the very end of the reduction sequence. Removed flakes exhibit features characteristic of conchoidal fracturing, including striking platforms, bulbs of force, and occasionally eraillures (small secondary flakes detached from the flake's bulb of force). Flakes are often quite sharp, with distal edges only a few molecules thick when they have a feather termination. These flakes can be used directly as tools or modified into other utilitarian implements, such as spokeshaves and scrapers.

Microblade technology

Microblade technology is a period of technological development marked by the creation and use of small stone blades, which are produced by chipping silica-rich stones like chert, quartz, or obsidian. Blades are a specialized type of lithic flake that are at least twice as long as they are wide. An alternate method of defining blades focuses on production features, including parallel lateral edges and dorsal scars, a lack of cortex, a prepared platform with a broad angle, and a proximal bulb of percussion. Microblades are generally less than 50 mm long in their finished state.

Microburin

A microburin is a characteristic waste product from manufacture of lithic tools — sometimes confused with an authentic burin — which is characteristic of the Mesolithic, but which has been recorded from the end of the Upper Paleolithic until the Calcolithic. This type of lithic artifact was first named by Henri Breuil who defined it as "a type of angular, smooth, with a terminal retouch in the form of a small notch". Breuil initially thought that the microburins had a functional use as a type of microlithic burin. However, he later came to realize that the manufacturing technique was different from that of the burin and that they could be waste products from the manufacture of microliths, but they may have occasionally been reused for a useful purpose.

A microburin is a fragment of a lithic flake, or more precisely, of a lithic blade, that shows on its upper face the beginnings of a notch terminating in an oblique flection (whose surface can only be seen from the lower side) that ends in a very acute trihedral apex. As stated earlier, it was thought that microburins were functional microliths, but carving experiments, along with the reassembly of pieces with perfectly aligned edges have demonstrated that they were a characteristic waste of a technique called microburin technique, or more correctly microburin blow technique, following a study of thousands of microburins originating from a variety of

saharan sites. Jacques Tixier noted that none of the pieces showed traces of intentional use, this finding confirms the finding of the analysis of European pieces.

Examples found in Europe can be seen on this page : http://www.archeobase.be/page_microburins_meso.html. They are related with Mesolithic hunters of the Walloon region of Belgium ap. 9,000 years ago.

There is also a particular type of microburin named after Krukowski that is from a carving accident and not a waste byproduct.

Natural (archaeology)

In archaeology, natural is a term to denote a layer (stratum) in the stratigraphic record where there is no evidence of anthropogenic activity. While there may be "natural" layers interbedded with archaeologically interesting layers, such as when a site was abandoned for long periods of time between occupations by man, the top (the horizon) of the natural layer below which there is no anthropogenic activity on site, and thus where the archaeological record chronologically begins, is the sought-for point to terminate digging. This final natural layer is often the underlying geological makeup of the site that was formed by geological processes. It is the goal of complete excavation to remove the entirety of the archaeological record all the way to the final "natural", thus leaving only the natural deposits of pre-human activity on site. If the excavation is related to development, the impact assessment may stipulate excavation will cease at a certain depth, because the nature of the development will not disturb remains below a certain level; such an excavation may not reach a natural or sterile layer. Thus one always has to overdig a site (dig past the top of the natural) in order to establish the natural.

Striking platform

In lithic reduction, the striking platform is the surface on the proximal portion of a lithic flake on which the detachment blow fell; this may be natural or prepared. Types of striking platforms include:

Cortex, which consists of an area of cortex used as a platform during initial reduction;

Single-faceted, consisting of a flat platform at right angles to the dorsal surface of the flake and most often associated with conchoidal fractures;

Double-faceted, a variety of multifaceted, prepared platform, also characteristically flat and associated with conchoidal fractures;

Multifaceted, with three or more facets to the platform;

Lipped, a platform type resulting from soft hammer biface reduction; and

Crushed, which occurs when the platform was crushed beyond easy recognition by the detachment blow.

Termination type

In lithic reduction, termination type is a characteristic indicating the manner in which the distal end of a lithic flake detaches from a core (Andrefsky 1998:18). Common types include:

Step/snap termination – these occur when a flake snaps or breaks during removal, resulting in an abrupt right-angle break.

Hinge termination – results when the applied force rolls away from the core or objective piece, creating a rounded or blunted distal end.

Overshot/outrepasse/plunging termination - occurs when the applied force dips and removes a section of the opposite margin of the artifact or the distal end of the core. Also referred to as a reverse hinge termination.

Perverse termination - "twisting" breaks resulting from when the applied force is redirected through the material in a helical fashion;

Feather/monotomic termination – a smooth termination that results in a feathered distal end. The distal ends of these flakes are only a few molecules thick, are extremely sharp, and indicate a flawless detachment. These are the intended results of some lithic reduction techniques, and are very desirable for opportunistic tool use that does not require retouching or sharpening.

Uniface

In archeology, a uniface is a specific type of stone tool that has been flaked on one surface only. There are two general classes of uniface tools: modified flakes—and formalized tools, which display deliberate, systematic modification of the marginal edges, evidently formed for a specific purpose.

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