Lithic reduction - AbsoluteAstronomy.com

Lithic reduction involves the use of a hard hammer precursor, such as a hammerstone

Hammerstone

In archaeology, a hammerstone is a hard cobble used to strike off lithic flakes from a lump of tool stone during the process of lithic reduction. The hammerstone is a rather universal stone tool which appeared early in most regions of the world including Europe, India and North America...

, a soft hammer fabricator (made of wood

Wood

Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...

, bone

Bone

Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They 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...

or antler

Antler

Antlers are the usually large, branching bony appendages on the heads of most deer species.-Etymology:Antler originally meant the lowest tine, the "brow tine"...

), or a wood or antler punch to detach lithic flake

Lithic flake

In 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 as debitage. The objective piece, or the rock being reduced by the removal of flakes, is known as a core. Once the proper...

s from a lump of tool stone

Tool stone

The term tool stone has multiple meanings.In archaeology, a tool stone is a type of stone that is used to manufacture stone tools.Alternatively, the term can be used to refer to stones used as the raw material for tools....

called a lithic core

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 percussor such...

(also known as the "objective piece"). 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

Projectile point

In archaeological terms, a projectile point is an object that was hafted to a projectile, such as a spear, dart, or arrow, or perhaps used as a knife....

, knife, or other object. Flakes of regular size that are at least twice as long as they are broad are called blade

Blade (archaeology)

In archaeology a blade is a type of stone tool created by striking a long narrow flake from a stone core.Blades are defined as being flakes that are at least twice as long as they are wide and that have parallel or subparallel sides and at least two ridges on the dorsal side...

s. Lithic tools produced this way may be bifacial

Biface

In archaeology, a biface is a two-sided stone tool and is used as a multi purposes knife, manufactured through a process of lithic reduction, that displays flake scars on both sides. A profile view of the final product tends to exhibit a lenticular shape...

(exhibiting flaking on both sides) or unifacial

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...

(exhibiting flaking on one side only).

Cryptocrystalline

Cryptocrystalline

Cryptocrystalline is a rock texture made up of such minute crystals that its crystalline nature is only vaguely revealed even microscopically in thin section by transmitted polarized light. Among the sedimentary rocks, chert and flint are cryptocrystalline. Carbonado, a form of diamond, is also...

or amorphous stone such as chert

Chert

Chert is a fine-grained silica-rich microcrystalline, cryptocrystalline or microfibrous sedimentary rock that may contain small fossils. It varies greatly in color , but most often manifests as gray, brown, grayish brown and light green to rusty red; its color is an expression of trace elements...

, flint

Flint

Flint is a hard, sedimentary cryptocrystalline form of the mineral quartz, categorized as a variety of chert. It occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones. Inside the nodule, flint is usually dark grey, black, green, white, or brown in colour, and...

, obsidian

Obsidian

Obsidian is a naturally occurring volcanic glass formed as an extrusive igneous rock.It is produced when felsic lava extruded from a volcano cools rapidly with minimum crystal growth...

, and chalcedony

Chalcedony

Chalcedony is a cryptocrystalline form of silica, composed of very fine intergrowths of the minerals quartz and moganite. These are both silica minerals, but they differ in that quartz has a trigonal crystal structure, while moganite is monoclinic...

, as well as other fine-grained stone material, such as rhyolite

Rhyolite

This page is about a volcanic rock. For the ghost town see Rhyolite, Nevada, and for the satellite system, see Rhyolite/Aquacade.Rhyolite is an igneous, volcanic rock, of felsic composition . It may have any texture from glassy to aphanitic to porphyritic...

, felsite

Felsite

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 petrographic examination or chemical analysis for more precise definition...

, and quartzite

Quartzite

Quartzite is a hard metamorphic rock which was originally sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to gray, though quartzites often occur in various shades of pink...

, were used as a source material for producing stone tools. As these materials lack natural planes of separation

Cleavage (crystal)

Cleavage, in mineralogy, is the tendency of crystalline materials to split along definite crystallographic structural planes. These planes of relative weakness are a result of the regular locations of atoms and ions in the crystal, which create smooth repeating surfaces that are visible both in the...

, conchoidal fracture

Conchoidal fracture

Conchoidal fracture describes the way that brittle materials break when they do not follow any natural planes of separation. Materials that break in this way include flint and other fine-grained minerals, as well as most amorphous solids, such as obsidian and other types of glass.Conchoidal...

s occur when they are struck with sufficient force. The propagation of force through the material takes the form of a Hertzian cone

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...

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

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.

Removed flakes exhibit features characteristic of conchoidal fracturing, including striking platform

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...

s, bulbs of force, and occasionally eraillure

Eraillure

In lithic analysis , an eraillure is a small secondary flake removed from a lithic flake's bulb of force, which is a lump left on the ventral surface of a flake after it is detached from a core of tool stone during the process of lithic reduction...

s (small secondary flakes detached from the flake's bulb of force). 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 spokeshave

Spokeshave

A spokeshave is a tool used to shape and smooth wooden rods and shafts - often for use as wheel spokes, chair legs ,, self bows,and arrows. It can also be used to carve canoe paddles.-Modern:...

s and scraper

Scraper (archaeology)

In archaeology, scrapers are unifacial tools that were used either for hideworking or woodworking purposes. Whereas this term is often used for any unifacially flaked stone tool that defies classification, most lithic analysts maintain that the only true scrapers are defined on the base of...

Percussion reduction

Percussion reduction, or percussion flaking, refers to removal of flakes by striking a core

Lithic core

or other objective piece, such as a partially formed tool, with a hammer or percussor. Alternatively, the objective piece can also be struck against a stationary anvil

Anvil

An anvil is a basic tool, a block with a hard surface on which another object is struck. The inertia of the anvil allows the energy of the striking tool to be transferred to the work piece. In most cases the anvil is used as a forging tool...

-stone, known as bipolar

Bipolar

-Medicine:* Bipolar cell* Bipolar cell of the retina* Bipolar disorder** Bipolar I disorder** Bipolar II disorder** Bipolar NOS* Bipolar spectrum-Astronomy:* Bipolar nebula, a two-lobed, axially symmetric nebula...

percussion. Percussors are traditionally either a stone cobble or pebble, often referred to as a hammerstone

Hammerstone

, or a billet made of bone, antler, or wood. 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.

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

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

Conchoidal fracture

on the detached flake, such as the bulb of percussion and compression rings.

Soft-hammer percussion

Soft-hammer percussion involves the use of a billet, usually made of wood, bone or antler as the percussor. 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 bent 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.

Pressure flaking

Pressure flaking is a method of trimming the edge of a stone tool

Stone tool

A stone tool is, in the most general sense, any tool made either partially or entirely out of stone. Although stone tool-dependent societies and cultures still exist today, most stone tools are associated with prehistoric, particularly Stone Age cultures that have become extinct...

by removing small lithic flake

Lithic flake

s by pressing on the stone with a sharp instrument rather than striking it with a percussor. 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. Copper retoucheurs to facilitate this process were widely employed in the Early Bronze Age – and may therefore be associated with Beaker Culture

Beaker culture

The Bell-Beaker culture , ca. 2400 – 1800 BC, is the term for a widely scattered cultural phenomenon of prehistoric western Europe starting in the late Neolithic or Chalcolithic running into the early Bronze Age...

in northwestern Europe.

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. The tip of the flaking tool is placed against the edge of the stone tool and pressed hard, removing a small linear or lunate

Lunate

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 removed from a stone tool during the process of pressure flaking....

flake from the opposite side. In some instances, a hammer and punch is used while the tool is held down with a vise. 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

Basalt

Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

or quartzite

Quartzite

. Great care must be taken during pressure flaking so that perverse fractures

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...

that break the entire tool do not occur. Occasionally, outrepasse
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...

breaks occur when the force propagates across and through the tool in such a way that the entire opposite margin is removed.

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 notch

Notch

Notch may refer to:* The nock of an arrow* Notch , a Hip hop, R&B, reggae, dancehall and reggaeton artist* Notch signaling pathway, a cell signaling system present in most multicellular organisms...

es where the objective piece could be bound more securely to the shaft of the weapon

Weapon

A weapon, arm, or armament is a tool or instrument used with the aim of causing damage or harm to living beings or artificial structures or systems...

or tool

Tool

A tool is a device that can be used to produce an item or achieve a task, but that is not consumed in the process. Informally the word is also used to describe a procedure or process with a specific purpose. Tools that are used in particular fields or activities may have different designations such...

and increasing the object's utility.

An archaeological discovery in 2010 in Blombos Cave

Blombos Cave

Blombos Cave is a cave in a calcarenite limestone cliff on the Southern Cape coast in South Africa. It is an archaeological site made famous by the discovery of 75,000-year-old pieces of ochre engraved with abstract designs and beads made from Nassarius shells, and c. 80,000-year-old bone tools...

, South Africa

South Africa

The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

, places the use of pressure flaking by early humans to make stone tools back to 73,000 BCE, 55,000 years earlier than previously accepted. The previously accepted date, "no more than 20,000 years ago", was based upon the earliest evidence previously available, which derived from findings of the Upper Paleolithic

Upper Paleolithic

The Upper Paleolithic is the third and last subdivision of the Paleolithic or Old Stone Age as it is understood in Europe, Africa and Asia. Very broadly it dates to between 40,000 and 10,000 years ago, roughly coinciding with the appearance of behavioral modernity and before the advent of...

Solutrean

The Solutrean industry is a relatively advanced flint tool-making style of the Upper Palaeolithic, from around 22,000 to 17,000 BP.-Details:...

culture in France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

and Spain

Spain

Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

Blank

A blank is a thick, shaped stone biface

Biface

of suitable size and configuration for refining into a stone tool

Stone tool

. Blanks are the beginning products of lithic reduction, and during prehistoric times were often created for trade or later refinement at another location. Blanks were often formed through the initial reduction of lumps of tool stone

Tool stone

at simple quarries

Quarry

A quarry is a type of open-pit mine from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone, construction aggregate, riprap, sand, and gravel. They are often collocated with concrete and asphalt plants due to the requirement...

, often no more than easily accessible outcroppings of the local tool stone (although this was certainly not the case at Grimes Graves

Grimes Graves

Grime's Graves is a large Neolithic flint mining complex near Brandon in England close to the border between Norfolk and Suffolk. It was worked between around circa 3000 BC and circa 1900 BC, although production may have continued well into the Bronze and Iron Ages owing to the low cost of flint...

in England). Sometimes the shape of the blank hints at the shape of the final tool it will become, but this is not always the case. A blank may consist of either a large, unmodified flake or a reduced core, often with a rough subtriangular or lanceolate shape. Rough chopping tools, derived by removing a few flakes along one edge of the cobble, can also be considered to fall into this group.

Preform

A preform is the rough, incomplete and unused basic form of a stone tool

Stone tool

. Typically, a preform is the shaped remnant of a lithic core

Lithic core

. Larger and thicker than the intended tool, it lacks the final trimming and refinement that is present in the completed artifact

Artifact (archaeology)

An artifact or artefact is "something made or given shape by man, such as a tool or a work of art, esp an object of archaeological interest"...

. Sometimes basic features such as stems and notches have been initiated. In most cases, the term refers to incomplete projectile point

Projectile point

In archaeological terms, a projectile point is an object that was hafted to a projectile, such as a spear, dart, or arrow, or perhaps used as a knife....

Percussion reduction

Hard-hammer percussion

Soft-hammer percussion

Pressure flaking

Blank

Preform

See also