Lithic reduction - Citizendia

The Levallois technique of flint-knapping

Lithic 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 a lump of tool stone called a lithic core (also known as the "objective piece"). 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 Wood is hard fibrous lignified structural tissue produced as secondary Xylem in the stems of Woody plants notably trees but also shrubs 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 Antlers are the usually large and complex horn -like appendages of most Deer species mostly worn by males only for some species such as Caribou by both Archaeology, a lithic flake is a "portion of rock removed from an objective piece by percussion or pressure" and may also be referred to as a chip or spall or collectively In Archaeology, a tool stone is a type of stone that is used to manufacture Stone tools Generally speaking tools that require a sharp edge are made using Cryptocrystalline In Archaeology, a lithic core is a distinctive artifact that results from the practice of Lithic reduction. 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, on 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. 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 Flakes of regular size that are at least twice as long as they are broad are called blades. In Archaeology a blade is a type of Stone tool created by striking a long narrow flake from a stone core. Lithic tools produced this way may be bifacial (exhibiting flaking on both sides) or unifacial (exhibiting flaking on one side only). In archaeology a biface is a two-sided Stone tool, manufactured through a process of Lithic reduction, that displays flake scars on both sides In Archeology, a uniface is a specific type of stone tool that has been flaked on one surface 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. Cryptocrystalline is a rock texture which is so finely crystalline being made up of such minute Crystals that its crystalline nature is only vaguely revealed Chert (ˈtʃɝt is a fine-grained Silica -rich Microcrystalline, Cryptocrystalline or Microfibrous Sedimentary rock that may contain Flint (or flintstone) is a hard sedimentary Cryptocrystalline form of the Mineral Quartz, categorized as a variety of Chert Obsidian is a naturally occurring Glass formed as an extrusive Igneous rock. Chalcedony is a Cryptocrystalline form of Silica, composed of very fine intergrowths of the minerals Quartz and Moganite. This page is about a volcanic rock For the ghost town see Rhyolite Nevada, and for the satellite system see Rhyolite/Aquacade. Felsite is a very fine grained Volcanic rock that may or may not contain larger Crystals Felsite is a field term for a light colored rock that typically requires Quartzite (from German Quarzit) not to be confused with the Mineral Quartz, is a hard Metamorphic rock which was originally As these materials lack natural planes of separation, conchoidal fractures occur when they are struck with sufficient force. Cleavage, in Mineralogy, is the tendency of crystalline materials to split along definite planes creating smooth surfaces of which there are several named types Conchoidal Fracture describes the way that Brittle materials break when they do not follow any natural planes of separation. 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. 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 Archaeology, a lithic flake is a "portion of rock removed from an objective piece by percussion or pressure" and may also be referred to as a chip or spall or collectively This process is predictable, and allows the flintknapper to control and direct the application of force so as to shape the material being worked.

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). 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 In Lithic analysis (a subdivision of Archaeology) an eraillure is a small secondary flake removed from a Lithic flake 's bulb of force, which 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 Flakes are often quite sharp, with distal edges only a few molecules thick, and can be used directly as tools or modified into other utilitarian implements, such as spokeshaves and scrapers. A spokeshave is a Tool used to shape and smooth wooden rods and shafts - often for use as Wheel spokes Chair legs (particularly complex shapes such

1 Techniques
- 1.1 Percussion reduction
  - 1.1.1 Hard-Hammer percussion
  - 1.1.2 Soft-Hammer percussion
- 1.2 Pressure flaking
2 References
3 See also

Techniques

Percussion reduction

Percussion reduction, or percussion flaking, refers to removal of flakes by striking a core or other objective piece, such as a partially formed tool, with a hammer or percussor. In Archaeology, a lithic core is a distinctive artifact that results from the practice of Lithic reduction. Alternatively, the objective piece can also be struck against a stationary anvil-stone, known as bipolar percussion. An anvil is a manufacturing tool made of a hard and massive block of stone or metal used as a support for Chiseling and Hammering other objects such as in Percussors are traditionally are either a stone cobble or pebble, often referred to as a hammerstone, or a billet made of bone, antler, or wood. 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, flakes are struck from a core using a punch, in which case the percussor never actually makes contact with the objective piece. This technique is referred to as indirect percussion. (Andrefsky 2004:12)

An example of hard hammer percussion.

Hard-Hammer percussion

Hard hammer techniques are generally used to remove large flakes of stone. Early flintknappers and hobbyists replicating their methods often use cobbles of very hard stone, such as quartzite. This technique can be used by flintknappers to remove broad flakes that can be made into smaller tools. This method of manufacture is believed to have been used to make some of the earliest stone tools ever found, some of which date from over 2 million years ago.

It is the use of hard-hammer percussion that most often results in the formation of the typical features of conchoidal fracture on the detached flake, such as the bulb of percussion and compression rings (Cotterell and Kamminga 1987:986)

An example of soft hammer percussion

Soft-Hammer percussion

Soft-hammer percussion involves the use of a billet, usually made of wood, bone or antler as the percussor. Conchoidal Fracture describes the way that Brittle materials break when they do not follow any natural planes of separation. 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 Flakes produced in this manner are generally smaller and thinner than those produced by hard-hammer flaking, thus, soft-hammer flaking is often used after hard-hammer flaking in a lithic reduction sequence to do finer work.

In most cases, the amount of pressure applied to the objective piece in soft-hammer percussion is not enough for the formation of a typical conchoidal fracture. Rather, soft-hammer flakes are most often produced by what is referred to as a bending fracture, so-called because the flake is quite literally bended or "peeled" from the objective piece. Flakes removed in this manner lack a bulb of percussion, and are distinguished instead by the presence of a small lip where the flake's stiking platform has separated from the objective piece (Andrefsky 2005:18-20; Cotterell and Kamminga 1987:690). 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

Pressure flaking

An example of pressure flaking

In lithic reduction, pressure flaking is a method of trimming the edge of a stone tool by removing small lithic flakes by pressing on the stone with a sharp instrument rather than striking it with a percussor. A stone tool is in the most general sense any Tool made of stone. Archaeology, a lithic flake is a "portion of rock removed from an objective piece by percussion or pressure" and may also be referred to as a chip or spall or collectively This method, which often uses punches made from bone or antler tines (or, among modern hobbyists, copper punches or even nails), provides a greater means of controlling the direction and quantity of the applied force than when using even the most careful percussive flaking. Usually, the objective piece is held clasped in the flintknapper's hand, with a durable piece of fabric or leather protecting the flintknapper's palm from the sharpness of the flakes removed. A knapper is a person who shapes Flint, Chert, Obsidian or other stone through the process of knapping or Lithic reduction to manufacture The tip of the flaking tool is placed against the edge of the stone tool and pressed hard, removing a small linear or lunate flake from the opposite side. Lunate is a term meaning crescent or moon-shaped In the specialized terminology of Lithic reduction, a lunate flake is a small crescent-shaped flake In some instances, a hammer and punch is used while the tool is held down with a vice. The process also involves frequent preparation of the edge to form better platforms for pressing off flakes. This is usually accomplished with abraders made from a coarse-grained stone such as basalt or quartzite. Basalt (bəˈsɔːlt ˈbeisɔːlt ˈbæsɔːlt is a common Extrusive Volcanic rock. Quartzite (from German Quarzit) not to be confused with the Mineral Quartz, is a hard Metamorphic rock which was originally Great care must be taken during pressure flaking so that perverse fractures that break the entire tool do not occur. 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 Occasionally, outrepasse breaks occur when the force propagates across and through the tool in such a way that the entire opposite margin is removed. 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

The use of pressure flaking facilitated the early production of sharper and more finely-detailed tools. Pressure flaking also gave toolmakers the ability to create notches where the objective piece could be bound more securely to the shaft of the weapon or tool and increasing the objects utility. A weapon is a Tool used either in Hunting, or attack or defence in Combat for the purpose of subduing enemy personnel or to destroy enemy weapons A broader definition of a tool is an entity used to interface between two or more domains that facilitates more effective action of one domain upon the other

References

Andrefsky, W. (2005) Lithics: Macroscopic Approaches to Analysis. Cambridge: Cambridge University Press. ISBN 0521615003
Cotterell, B. and Kamminga, J. (1987) The Formation of Flakes. American Antiquity 52:675-708

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