Lithics Glossary

Term / Name	Definition
Glossary Supplement 1	Click Supplement-1 for detailed information on the Lithics Diagnostic Tools Class-2 Slide-15 page.
Abrading	During projectile point creation, this is the "sanding down" or cleaning off of jagged edges remaining from broken-off flakes. If this isn't done the thin, un-abraded material will be crushed with the next Precussor blow.
Acheulean	Acheulean, from the French acheuléen after the type site of Saint-Acheul, is an archaeological industry of stone tool manufacture characterized by the distinctive oval and pear-shaped "hand axes" associated with Homo erectus and derived species such as Homo heidelbergensis. It relates to or denotes the main Lower Paleolithic culture in Europe (preceding the Mousterian), represented by hand-axe industries, and dated to about 1,500,000 - 150,000 years ago. To see an image of an Acheulean tool, please click .
Aeolian	Aeolian landforms are shaped by the wind (named for the Greek God of wind, Aeolus). Aeolian processes create a number of distinct features, through both erosion and deposition of sediment, including: Sand dunes, Loess Deposits, Ventifact, Yardangs, Deflation Hollow or Blowout, and Desert Pavement. Aeolian processes involve erosion, transportation, and deposition of sediment by the wind. These processes occur in a variety of environments, including the coastal zone, cold and hot deserts, and agricultural fields. Common features of these environments are a sparse or nonexistent vegetation cover, a supply of fine sediment (clay, silt, and sand), and strong winds. Aeolian processes are responsible for the emission and/or mobilization of dust and the formation of areas of sand dunes. They largely depend on other geologic agents, such as rivers, glaciers, and waves, to supply sediment for transport.
Alluvium / Alluvial	Alluvium (from Latin alluvius, from alluere 'to wash against') is loose clay, silt, sand, or gravel that has been deposited by running water in a stream bed, on a floodplain, in an alluvial fan or beach, or in similar settings. Alluvium is also sometimes called alluvial deposit. Alluvium is typically geologically young and is not consolidated into solid rock. Sediments deposited underwater, in seas, estuaries, lakes, or ponds, are not described as alluvium.
Amorphous	In condensed matter physics and materials science, an amorphous solid is a solid that lacks the long-range order that is characteristic of a crystal. Glass is amorphous, salt and a diamond are not.
Andrefsky, Jr., William	Dean, Graduate School, Washington State University, Pullman, WA. https://anthro.wsu.edu/faculty-and-staff/william-andrefsky/.
Argellite	Argillite is a fine-grained sedimentary rock composed predominantly of indurated clay particles. Argillaceous rocks are basically lithified muds and oozes. They contain variable amounts of silt-sized particles. The argillites grade into shale when the fissile layering typical of shale is developed.
B.C.E. (vs B.C.)	This is an example of the evolution of human time-tracking, and they mean exactly the same thing as AD (anno Domini) and BC (before Christ). Simply put, BCE (Before Common Era) is a secular version of BC (before Christ).
B.P.	B.P. (Before the Present) is the number of years before the present. Because the present changes every year, archaeologists, by convention, use A.D. 1950 as their reference. So, 2000 B.P. is the equivalent of 50 B.C.
Biface Tools	Bifaces are objective pieces that have been extensively modified, and have two sides or faces that meet to form a single edge that circumscribes the entire artifact; both faces show evidence of previous flake removals.
Billet	A short, heavy club, or cudgel.
Bioturbation	The reworking of soils and sediments by animals or plants. It includes burrowing, ingestion, and defecation of sediment grains.
Bipolar Flaking	The object to be worked is placed on a stationary surface (anvil) and then struck with a handheld hammer.
Bird Stone	Bird stones are prehistoric, abstract stone carvings made by Native Americans. The artifacts were a common inclusion in graves and thought to have ceremonial importance. They are noted for their distinctive simplicity and beauty. They first appeared in the middle Archaic period around 5,000 years ago and continued into the early Woodland period to about 2,500 years before present. The exact purpose of these artifacts is not known, but most have a small hole drilled at the base of the neck and another at the aft end, presumably for mounting. Some theories suggest they were part of an atlatl, in addition to their ceremonial uses. A new theory recently arising from an amateur archaeologist focused on Native American fiber processing, is the bird stone was a tool used for mat-making and weaving. Many stones have been found near waterways and swamp areas where reeds grow, these areas being where materials for mat-making were collected and processed. The holes in the base were potentially used for reed straightene
Brittle	Material breaks relatively easily and cannot deform.
Burin	The term burin refers to a tool used by engravers that has a thin, pointed blade and is used to etch or cut. Click for a larger view of a modern burin used for engraving and a Paleolithic burin. Paleolithic burins exhibit a feature called a burin spall - a sharp, angled point formed when a small flake is struck obliquely from the edge of a larger stone flake.
Chi-Square Statistic	A test which is used to help determine if observed results are in line with expected results, and to rule out that observations are due to chance. For information on it, please click https://www.investopedia.com/terms/c/chi-square-statistic.asp.
Conchoidal Fracture	The term conchoidal is used to describe a fracture with smooth, curved surfaces that resemble the interior of a seashell; it is commonly observed in quartz and glass.Reference Lithics Class, Day-1, Slide 10 .
Core	An Objective Piece from which flakes have been removed. The Core is reduced as Flakes are progressively removed, until its utility to supply flakes is exhausted, at which point it is discarded.
Core Size Value (CSV)	(see Maximum Linear Dimension)
Cortex	In lithic analysis in archaeology the cortex is the outer layer of rock formed on the exterior of raw materials by chemical and mechanical weathering processes. It is often recorded on the dorsal surface of flakes using a three class system: primary, secondary, and tertiary. The amount of cortex present on artifacts in an archaeological assemblage may indicate the extent of lithic reduction that has occurred. Primary, secondary, and tertiary designations for flakes are generally determined by relative amounts of cortex presented on the dorsal surface. Differences in how archaeologists classify the amount of cortex and the results of experimental archaeological tests demonstrating moderate correlation between amount of cortex and stage of reduction, have limited the validity of assumptions based on amount of cortex solely.
Cryptocrastalline	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 cryptocrystalline.
Debitage	Detached Pieces that are discarded during the Reduction Process.
Detached Pieces	Items removed from the Objective Piece. Detached pieces are removed from the Objective Piece by Percussion Flaking, Pressure Flaking or natural wear.
Diagenesis	The physical and chemical changes occurring during the conversion of sediment to sedimentary rock.
Elastic	Material possesses a little flexibility, returning to original shape if not deformed too mucn.
End, Distal	The bottom.
End, Proximal	The top.
Extrusive Igneous Rock Formation	Extrusive rock refers to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out onto the surface as lava or explodes violently into the atmosphere to fall back as pyroclastics or tuff. In contrast, intrusive rock refers to rocks formed by magma which cools below the surface.
Fissility	A general term for the property possessed by some rocks of splitting easily into thin layers along closely spaced, roughly planar, and approximately parallel surfaces, such as bedding planes in shale or cleavage planes in schist; its presence distinguishes shale from mudstone.
Flakes	(see Detached Pieces)
Flakes / Fragments Medial	These flakes include all broken pieces that have no Proximal end and a stepped distal end.
Flakes / Fragments Distal	When a detached piece snaps into two fragments, one wil contain the striking platform (proximal end). The other piece will have the distal end, and is called a distal fragment.
Flakes / Fragments Proximal	These flakes may be whole or broken, but all contain an intact point of applied force or striking platform.
Flintknapping	Common terms for making flaked stone tools
fMRI	Functional Magnetic Resonance Imaging or functional MRI measures brain activity by detecting changes associated with blood flow. This technique relies on the fact that cerebral blood flow and neuronal activation are coupled. When an area of the brain is in use, blood flow to that region also increases.
Foliated Rock	Foliated means the parallel arrangement of certain mineral grains that gives the rock a striped appearance.) Foliation forms when pressure squeezes the flat or elongate minerals within a rock so they become aligned.
Friable / Friability	In materials science, friability describes the tendency of a solid substance to break into smaller pieces under duress or contact, especially by rubbing. The opposite of friable is indurate.
Geologic Epoch: Holocene	The Holocene is the name given to the last 11,700 years of the Earth's history - the time since the end of the last major glacial epoch, or "ice age." Since then, there have been small-scale climate shifts - notably the "Little Ice Age" between about 1200 and 1700 A.D. - but in general, the Holocene has been a relatively warm period in between ice ages.
Geologic Epoch: Pleistocene	The geologic epoch before the Holocene. For a complete list of the geologic epochs, please click Epochs.
Hackly Fracture	Hackly fracture is breakage along jagged surfaces.
Haft Element	The location on a biface that is used as an attachment area onto a handle of some kind; in contrast to the blade or bit or the working end that is used as a tool for cutting, scraping, or puncturing, etc. The haft element is often inserted into a socket or notch and then wrapped or covered with a mastic to form a tight bond. Because the haft element is covered, it is protected from day-to-day wear.
Hafting	Attaching a projectile point to a shaft.
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. For additional information on the Hertzian Cone, please click Hertzian Info.
Homogeneous	Chemically and structurall similar throughout, consisting of amorphous or isotropic cryptocrystalline structure, and lacking direction-dependent properties such as bedding planes, fissures, cracks or inclustions.
Hornfel Rock	Hornfels is the group name for a set of contact metamorphic rocks that have been baked and hardened by the heat of intrusive igneous masses and have been rendered massive, hard, splintery, and in some cases exceedingly tough and durable.
Induration	Induration is the hardening of rocks by heat or baking; also the hardening of sediments through cementation or compaction, or both, without the introduction of heat.
Intrusive Igneous Rock Formation	Intrusive rock is formed when magma penetrates existing rock, crystallizes, and solidifies underground to form intrusions, such as batholiths, dikes, sills, laccoliths, and volcanic necks. Intrusion is one of the two ways igneous rock can form. The other is extrusion, such as a volcanic eruption or similar event.
Isotropic Materials	These have identical material properties in all directions at every given point. This means that when a specific load is applied at any point in the x, y or z axis, the material will exhibit the same strength, stress, strain, and Young's modulus and hardness.
Kame	KAMES are irregular hills of sand and gravel with steep slopes. Glaciers pick up rock debris as the ice flows along. Glacial meltwaters carry sand and gravel from the glacier.
Kanpping	(see Flintnapping)
Levallois Core	A method of creating stone tools by first striking flakes off the stone, or core, along the edges to create the prepared core and then striking the prepared core in such a way that the intended tool is flaked off with all of its edges pre-sharpened.
Lithic	In archaeology, lithic technology includes a broad array of techniques used to produce usable tools from various types of stone.
Macrolith	A stone tool about a foor (30 cm) long.
Macroscopic	Visible to the naked eye or a hand lens ( < 10 X magnification ).
Maximum Linear Dimension (MLD)	Most cores, regardless of amorphous their shape, have one linear dimension that is easily recognized as the greatest (its MLD). That dimension, multiplied by its weight, provides a uniform measure of its size, its Core Size Value.
Metamorphic Rock	Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock is subjected to temperatures greater than 150 to 200 oC and, often, elevated pressure of 100 megapascals or more, causing profound physical or chemical changes.
Microlith	A tiny stone tool, often of geometric shape, made from a bladelet and mounted singly or in series as the working part of a composite tool or weapon, especially during late Upper Paleolithic and Mesolithic times.
Microscopic	So small as to be visible only through use of a microscope.
Microwear Analysis	Diagnostic process which attempts to determine the functions of stone tools by examining direct evidence in the form of use/wear on the tool surfaces, particularly near the edges.
Mohs Scale	The Mohs scale of mineral hardness is based on the ability of one natural sample of mineral to scratch another mineral visibly. The samples of matter used by Mohs are all different minerals. Minerals are chemically pure solids found in nature. Rocks are made up of one or more minerals. The hardness of a material is measured against the scale by finding the hardest material that the given material can scratch, or the softest material that can scratch the given material. For more information on the Mohs scale, please click https://en.wikipedia.org/wiki/Mohs_scale.
Moraine	A moraine is any accumulation of unconsolidated debris, sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions, and that has been previously carried along by a glacier or ice sheet.
Morphology, Lithic Flake	At its most basic level, lithic analyses involve an analysis of the artifact's Morphology (archaeology), the measurement of various physical attributes, and examining other visible features (such as noting the presence or absence of cortex, for example). Click 3-D Rendering for a 3-D rendering of a flake with its major parts identified.
Morphology, Stages	Morphology here can also related to the stages of development of the end product. In Lithics Class, Day-1, Slide 28 we see the various stages in the production of a projectile point. Each stage, however, can also be viewed in its own right, since in theory the result of each stage can fulfill a need of its own. What we see when we examine a point in the field is simply the final stage in the existence of this artifact.
MRI	Magnetic Resonance Imaging is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves to generate images of the organs in the body.
Objective Piece	That which is struck by a Percussor (a hammerstone or billet)to detach a flake. The starter material.
Obsidian Hydration Dating	Obsidian hydration dating (OHD) is a chronometric method based on measuring the water absorbed through a fresh surface of obsidian, and is widely used in the inter-mountain west. The method is more accurate than assigning dates based on projectile point typology but less accurate than radiocarbon. It is relatively inexpensive, and has the benefit of directly dating obsidian artifacts.
Oldowan	The Oldowan was a widespread stone tool archaeological industry in prehistory. These early tools were simple, usually made with one or a few flakes chipped off with another stone. It relates to or denotes an early Lower Paleolithic culture of Africa, dated to about 2.0 - 1.5 million years ago. It is characterized by primitive stone tools that are associated chiefly with Homo habilis. To see an image of an Oldowan tool, please click .
Paleosol	Paleosols are ancient soils, formed on landscapes of the past. Most paleosols have been buried in the sedimentary record, covered by flood debris, landslides, volcanic ash, or lava. Some paleosols, however, are still at the land surface but are no longer forming in the same way that they did under different climates and vegetation in the past. Some surface soils are paleosols, although most paleosols are buried soils.
Pedogenic / Pedogenesis	In terms of pedogenesis, plants are the soil-forming force that accelerates the development of the soil through an accumulation of organic matter at its surface and a deep modification of the soil surrounding the roots, the rhizosphere soil.
Percussion, Anvil	The core itself is struck against the anvil.
Percussion, Direct	The hammerstone blow is aimed directly at the raw materia.
Percussion, Indierct	An intermediate object (antler, stone, bone or wood) is placed on the raw material and used as a punch, which is then struck by the hammerstone. This technique enables highly precise blows, often producting punctiform Striking Platfoms.
Percussion, Pressure Flaking	Variant of Soft Percussion, using an antler tine or similar pointed object for fine, finish work.
Percussion, Soft	Percussion using a bone hammer or billet, which are softer than the Objective material.
Period Ranges: North American Native Peoples	For detailed breakdowns of the various periods and sub-periods, please click Periods.
Period: 1 Paleoindian	13,000 to 10,000 years ago,
Period: 2 Archaic	10,000 - 2,500 years ago.
Period: 3 Woodland	2,500 to 1,100 years ago.
Period: 4 Whittlesy	1,100 to 400 years ago.
Period: 5 Contact	400 to present
Phenocryst	A relatively large crystal embedded in a finer-grained or glassy igneous rock. The presence of phenocrysts gives the rock a porphyritic texture. Phenocrysts are represented most commonly by feldspar, quartz, biotite, hornblende, pyroxene and olivine.
Phytolith	Phytoliths are silica deposits that have been transported to various cells of growing plants. Often silica is transported by groundwater taken in by the plants and is deposited within plant structures and hardens to assume the shape of those structures. When plant materials are worked or processed with stone tools, the silica phytoliths may adhere to the surface of the tool and can be recognized under magnification. Sometimes the phytoliths are embedded within the silica polish formed along the cutting or scraing edge of tools. These inorganic remains survive in the archaeological record and are diagnostic to plants, and parts of plants.
Points, Dalton	Dalton points were generally lanceolate (leaf-shaped). The blade portion of the point was sometimes serrated, similar to a modern bread knife. The bottom, or haft, portion of the Dalton point was made to be concave at the base and tapered so that it would fit into a handle or a spear shaft.
Points, Perkiomen	The Perkiomen is a broad point with a small stem and a base that is usually convex. Generally, Perkiomen points are half as broad as long, and often asymmetrical. They are extremely thin for their width. The Perkiomen point dates to the end of the Late Archaic period.
Preform	The next-to-last step before the piece is finished.
Pressure Flaking	Placing a retouch object (antler, wood, bone or stone) against the edge of a blank (flake) and apply pressure inwards to remove small, precision flakes.
Projectile Point Elements	Click    for diagrams.
Projectile Points (CT)	Click CT Projectile Points for a chart by Lucianne Lavin (IAIS) of CT Projectile Point types; e.g. Snook Kill, in the "Related Web Sites" section this website. (While not directly related to lithics, that section also has a similar page by Lavin on CT Pottery Types.) The "Related Web Sites" index page can be accessed at Related Sites.
Punctiform	Marked by points or dots.
Reduction	The process of shaping an Objective Piece by detaching fragments.
Retouch, Bifacial	Both sides of the surface or tool are worked.
Retouch, Unifacial	Only on one face of a surface or tool.
Rhyolite, Rhyolitic Lavas	Rhyolitic lavas are viscous and tend to form thick blocky lava flows or steep-sided piles of lava called lava domes. Rhyolite magmas tend to erupt explosively, commonly also producing abundant ash and pumice.
Rock, Alibates Flint	Alibates Flint is a hard rock that has a sharp edge when shaped properly. Early toolmakers were able to chip and flake it into an astonishing variety of everyday tools of survival. Archeologists have found knives, hammers, chisels, drills, axes, awls, fishhooks, buttons, hoes, scrapers and gravers, as well as dart points or arrowheads - all made out of Alibates flint.
Rock, Argillite	Another name for poorly lithified argillites is mudstone. These rocks, although variable in composition, are typically high in aluminium and silica with variable alkali and alkaline earth cations. The term pelitic or pelite is often applied to these sediments and rocks.
Rock, Basalt	Basalt is a dark-colored, fine-grained, igneous rock composed mainly of plagioclase and pyroxene minerals. It most commonly forms as an extrusive rock, such as a lava flow, but can also form in small intrusive bodies, such as an igneous dike or a thin sill. It has a composition similar to gabbro.
Rock, Chert	Commonly called flint, chert is a fine-grained, noncrystalline sedimentary rock made up of silicon dioxide (SiO2). (The mineral quartz has the same chemical formula.) The only difference between chert and flint is color: flint is black or nearly black and chert tends to be white, gray, or pink and can be either plain, banded, or preserve fossil traces.
Rock, Concretions	Concretions are commonly misunderstood geologic structures. Often mistaken for fossil eggs, turtle shells, or bones, they are actually not fossils at all but a common geologic phenomenon in almost all types of sedimentary rock, including sandstones, shales, siltstones, and limestones. They form inside sediments before they harden into rocks, when they are still soft, as minerals within a sediment precipitate, sometimes in successive layers around a nucleus such as a shell or pebble. Rates of this formation vary, but can sometimes apparently be relatively rapid, over as short a period as months to years. Cracking them open can be fascinating, yielding shells, fossilized animals and fish, and who-knows-what else. To see a video on this, please click Cracking Concretions.
Rock, 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. The only difference between chert and flint is color: flint is black or nearly black and chert tends to be white, gray, or pink and can be either plain, banded, or preserve fossil traces.
Rock, Limestone	Limestone is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of CaCO?. Limestone forms when these minerals precipitate out of water containing dissolved calcium.
Rock, Mudstone	Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from shale by its lack of fissility. The term mudstone is also used to describe carbonate rocks that are composed predominantly of carbonate mud.
Rock, Obsidian	Obsidian is a naturally occurring volcanic glass formed when lava extruded from a volcano cools rapidly with minimal crystal growth. It is an igneous rock. Obsidian is produced from felsic lava, rich in the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium. In the "Reprints" section of this website there is an article on the "Obsidian Cliff" which appeared in the NY Times about a mountain in Yellowstone of this name, accessible by clicking Reprinted-NYT.
Rock, Porcelanite	Porcelanite is a hard, dense rock that takes its name from its resemblance to unglazed porcelain. Frequently porcellanite is an impure variety of chert containing clay and calcareous matter; when of this nature it is composed chiefly of silica
Rock, Quartz	Quartz is a hard, white or colorless mineral consisting of Silicon Dioxide, found qidely in igneous, metamorphic and sedimentary rocks. It is often colored by impurities (as in amethyst, citrine and cairngorm.
Rock, Quartzite	Quartzite is a very hard metamorphic rock that originated as sandstone. Through a process of high heating and pressurization sandstone is transformed into Quartzite, an extremely strong and durable natural stone.
Rock, Sandstone	Sandstone is a clastic sedimentary rock composed mainly of sand-sized silicate grains. Sandstones comprise about 20-25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar because they are the most resistant minerals to weathering processes at the Earth's surface.
Sickle Gloss	Sickle-gloss, or sickle sheen, is a silica residue found on blades such as sickles and scythes suggesting that they have been used to cut the silica-rich stems of cereals and forming an indirect proof for incipient agriculture. The gloss occurs from the abrasive action of silica in both wild and cultivated stems of cereal grasses, meaning the occurrence of reaping tools with sickle gloss doesn't necessarily imply agriculture.
Sickle Sheen	(see Sickle Gloss)
Spall	Spall are fragments of a material that are broken off a larger solid body of the same material.
Splintery Fracture	Splintery fracture is breakage into elongated fragments like splinters of wood
Strike Platform	The locations on the core and detached flake impacted by the Percussor.
Surface, Dorsal	On a Conchoidal flake, this is the opposite of the Ventral surface, and may show signs of the original texture of the rock or of previous flake removals or flake scars.
Surface, Ventral	On a Conchoidal flake, this is the surface that has broken away from the Objective piece, and is usually smooth and shows no evidence of previous flake removals. The Ventral side will always be a fresh break relative to the Dorsal side.
Termination, (all types) Flake	This is where the force dissipates and the crack progression terminates. It is dependent upon the direction of applied force, the amount of force applied, and the properties of the stone matrices.
Terminations, Feathered	Continuations of flake propagations. The distal edges can be extremely sharp.
Terminations, Hinge	These are caused by increases in the bending forces that redirect the force of impact to turn towards or away from the Objective piece.
Terminations, Plunging	(see Terminations, Hinge)
Terminations, Step	These result from a discontinuation of force flow - a breaking of the flake material.
Texture, Aphanitic	Aphanites are igneous rocks that are so fine-grained that their component mineral crystals are not visible to the naked eye. This geological texture results from rapid cooling in volcanic or hypabyssal environments.
Texture, Phaneritic	Of or relating to an igneous rock in which the crystals are so coarse that individual minerals can be distinguished with the naked eye. Phaneritic rocks are intrusive rocks that cooled slowly enough to allow significant crystal growth.
Texture, Phorphyritic	This texture describes a rock that has well-formed crystals visible to the naked eye, called phenocrysts, set in a very fine grained or glassy matrix, called the groundmass.
Tine	A prong or sharp point, such as that on a fork or antler.
Tools, Formal	The term encompasses a wide variety of tools that have undergone additional effort in production, whether the production occurred over the course of several resharpening or hafting episodes or in one episode of manufacturing from raw material to finished product.
Tools, Informal	Informal tools are unstandardized or casual with regard to form. Expediently made tools are included in this category. These tools are believed to have been manufactured, used, and discarded over a relatively short time period. These can also be characterized as situational gear or gear that is put to use in response to conditions rather than in anticipation of events or situations. This kind of technology is wasteful with regard to lithic raw material, and tends to produce tools that are simpler and have less formal patterning of shape or design.
Young's Modulus	The Young's (E) modulus, or the modulus of elasticity in tension or compression (i.e., negative tension), is a mechanical property that measures the tensile or compressive stiffness of a solid material when the force is applied lengthwise. It quantifies the relationship between tensile/compressive stress δ (force per unit area) and axial strain ε (proportional deformation) in the linear elastic region of a material and is determined using the formula: E = δ/ε.