GlossarySome archaeological terms have more than one meaning, and many terms have meanings or connotations applied by the individual investigator. This glossary defines key terms as they are used in this presentation.
alluvium: sediment deposited by a stream or river.
alluvial fan: a cone-shaped deposit of rock debris formed where a stream previously confined in a narrow canyon issues onto an open lowland. The decrease in flow depth and velocity causes deposition of the stream’s coarse bedload. Especially common on the fringes of arid mountains, where streamflows are episodic and bedloads are normally coarse, including gravel, cobbles, and boulders. Alluvial fans may be composed of water-transported alluvium, mudflows, bouldery debris flows, or a combination of these.
amorphous: having no definite form.
andesite: an extrusive volcanic rock (solidified from pasty lava) characterized by plagioclase feldspar. Chemically intermediate between basalt and rhyolite. The most common rock found in large stratovolcanoes.
andesite porphyry: andesite with conspicuously large feldspar crystals.
anvil: a rock base to support a core from which flakes are being detached by percussion; leaves diagnostic features on detached flakes.
arete: an acute (sharp) crest; a ridge between adjacent parallel flake scars.
argillic horizon: soil subsurface horizon made dense by clay translocated downward by percolating water, or formed in place in a zone of maximum moisture and mineral decay in the soil. Becomes more massive with time.
arkosic sand: sand having a high content of weatherable minerals such as orthoclase feldspar; often derived from weathered granite.
artifact: any object fashioned or modified by a human. The term includes debitage.
atlatl: throwing stick notched to propel a spear bearing a stone projectile point; lengthens the arm to vastly increase the force of a thrown spear. Used by Paleo-Indians and later Native Americans, as well as hunting cultures world-wide.
attribute: a trait; a significant, essential, or diagnostic characteristic.
backed: intentional blunting of the margin of a flake or blade that is opposite the sharpened edge, to facilitate use in the hand.
basal thinning: unifacial or bifacial removal of flakes from the proximal end of a flake tool to facilitate hafting. Normal in Paleo-Indian and Native American projectile points. Not seen in Manix and Calico lithic industry specimens.
basalt: iron-rich, chemically-basic extrusive igneous rock solidified from lava; initially dark gray to black in color, weathering to red in humid climates as iron is released and oxidized.
bi-directional cores: cores bearing flake scars indicating flake detachment from two directions.
biface: flaked or modified on both surfaces (dorsal and ventral) and/or along both sides of an edge. Face flaking, edge retouch, or use wear can be bifacial.
bipolar technique: technique of striking flakes from a core supported by a rock anvil. Recognizable by damage (chipping) at distal (anvil) end of flake or core.
blade, bladelet: parallel-sided flakes with a length at least 2.5 times the width. There must be at least one arete defining dorsal surface facets. Blades are at least 1.2 cm wide and 4.5 cm long. Width is the more definitive measure. Bladelets are less than 1.2 cm wide and 4.5 cm long.
blade core: multi-faceted cores with parallel aretes defining removal scars that are normally slightly concave.
blank: usable flake that is not modified, though large enough to yield a lithic artifact with further alteration. (see preform)
bola stones: spherical rocks linked with rawhide thongs and flung to knock down or entangle game animals or birds.
bulb: a characteristic convex or bulbous area on the ventral surface of a flake, located just below the proximal end of the flake, caused by impact on the proximal or platform area; variable in size and form.
bulb scar: scar on face of core ventral surface bulb, caused by energy passing through the detached flake bulb from the impact on the platform area.
burin: a small chisel-like flake or blade tool detached by striking from the platform (proximal) end of a finished blade or small core.
calcic horizon: subsurface soil horizon enriched by calcium carbonate translocated downward from the land surface or upward from a water table. May be visible as nodules, thin coatings on subsurface rocks, or massive crusts.
chalcedony: a fine-grained cryptocrystalline quartz phase without cleavage planes; appears waxy on a fresh break.
chert: a fine-grained cryptocrystalline siliceous material of varying color; lacks natural cleavage planes; appears dull and opaque on a fresh break.
cluster: an artificial (human-produced) concentration of debitage and other evidence of workshop activity, in contrast to randomly scattered specimens.
chopper: heavy core tool with edges presumed to be used for chopping; may be unifacial or bifacial.
cleaver: heavy core tool with a convex edge and blunt back; unifacial or bifacial.
cobbles: rocks measuring between 64 and 256 mm in diameter; usually somewhat rounded by abrasion during transport by streamflow.
compression rings: ripples concentric to the point of force on both flakes and negative flake scars of cores. Indicative of percussion rather than pressure flaking. Analagous to ripples made by a splash in water–here locked in stone.
concassage: natural fracture, crushing, and abrasion, in general producing rounded edges and apices rather than the sharp edges created by the controlled knapping process. Most commonly associated with transport by streamfloods and debris flows.
concavo-convex: inwardly-curving ventral surface and outwardly-curving dorsal surface.
conchoidal fracture: fracture surface with concentric ripples resembling the growth rings of bivalve shells; created by pressure or a sharp blow to amorphous brittle material. Ripples are semicircles around the point of impact.
control pit: excavated pit whose location is selected at random to determine the similarity or dissimilarity of geological deposits and the presence or absence of artifacts in quantities comparable to those found in a targeted excavation.
core: the primary rock mass from which flakes are removed by percussion or pressure flaking.
cortex: the natural outer surface of a rock; usually weathered to some degree. In arid regions, may appear unweathered but somewhat discolored by a thin patina of iron and manganese oxide (rock varnish).
country rock: typical rock of an area; at Calico, a general field term applied to volcanic and other rocks that are not fine-grained siliceous material.
dacite: siliceous extrusive igneous rock chemically intermediate between less siliceous andesite and more siliceous rhyolite.
debitage: rock debris from knapping or flaking; includes flakes, chunks, rejects, cores, and unfinished and broken tools.
debris flows: flows of rock material mobilized by water, that occur when high-intensity rains fall on mountain slopes lacking a complete vegetative cover. Debris flows are of two types: 1) rocks and boulders in a matrix of mud, and 2) angular rock fragments lacking a mud matrix (breccia flows). Where a partial vegetative cover is present, debris flows include brush and even sizeable trees. (See also mudflows)
decortication: removal of the surface or cortex. First stage decortication implies very little surface removal; second stage implies partial surface removal; third stage implies virtually total surface removal. Third stage decortication flakes are called interior flakes.
denticulate: having regular, toothlike projections; sawlike; usually fashioned by unifacial retouch.
desert pavement: a tight mosaic of rocks, from pebbles to boulders, left on old alluvial surfaces by the winnowing action of wind and water runoff that removes fine particles in areas of little to no vegetative cover; a lag deposit. Well-developed desert pavements occur only on surfaces more than 10,000 years old.
desert varnish: also known as “rock varnish;” a surface film of clay minerals colored by manganese and iron oxides that forms on long-exposed rock surfaces in dry regions. Typically brown (iron rich) to purplish black (manganese rich) when maximally developed.
diagnostic flake: a flake having attributes that indicate intentional removal from a source, such as a core, according to a pattern.
distal: the end of a flake or core opposite that which receives the flake-separating impact or pressure; normally the thinner end of a flake.
dorsal: back, outer, or upper surface; often convex or keeled; opposite the inner, down-side (ventral) surface.
end scraper: a scraper fashioned on the end of a blade or flake; encompasses the term “distal edge scraper.”
eoliths: most primitive stone tools used by humans or primates; in their natural state or crudely broken and difficult to distinguish as artifacts.
eraillure: a flake or chip formed between the flake bulb and the bulbar scar, usually adhering to the core in the bulbar scar. Evidence of percussion.
exotic stream: perennial stream that originates in non-desert mountains and subsequently passes through a desert, either terminating within the desert or eventually entering the sea.
face flaking: removal scars extending across and modifying the dorsal face and occasionally the ventral face of an artifact.
facets: elongate, approximately parallel, removal scars.
fanglomerate: coarse rock debris deposited as part of an alluvial fan; may be cemented subsequently, as with calcium carbonate.
faults: fractures in rocks that allow the rocks on one side to move with respect to the rocks on the other side; motion may be vertical, oblique, or horizontal. May be microscopic to thousands of kilometers in length and many km in vertical displacement.
feature: an assemblage of rocks, placed by humans, having a distinct form, outline, or quality.
fissures: cracks radiating from the point of force at the proximal end of a flake or core, and crossing compression rings on the flake and/or core.
flake, chip: 1) a fragment of rock removed from a larger flake, core, or block, by percussion or pressure; commonly sharp-edged. A flake has a diameter of 0.5 cm or more; a chip has a diameter of 0.5 cm or less. The general term “flake” can apply to both. A flake may be a simple fragment of debitage, a percussion flake, or a flake tool. 2) the verb “to flake” refers to the act of removing flakes, i.e., “knapping”–the process by which humans fashion tools from rocks by percussion or pressure.
flake knife: a flake evincing bifacial wear resulting from use as a cutting tool, but lacking retouch, i.e., a utilized flake.
force lines or lines of force: see compression rings.
function: normal or characteristic use or action.
geofacts: naturally-occurring rocks that superficially resemble lithic artifacts.
ground band: a characteristic band of maximally-developed manganese-rich rock varnish that separates the dorsal black patina from the ventral orange patina on rocks embedded in desert pavements. When this band is inclined relative to ground level the rock has been disturbed subsequent to varnish formation. (See rock varnish)
handaxe: characterized by a thick butt, bifacial flaking, ovoid form. “Handaxe” is a descriptive term. A basic handaxe is not a tool. Retouch modification determines the function of the object.
hard hammer: a stone used as a hammer in percussion flaking.
hinge flake: flake on which the distal end is rounded instead of thin and sharp. Force detaching the flake plunges downward and inward rather than running directly to a thin termination.
Holocene: the latest epoch of the Quaternary, usually taken as the most recent 10,000 years; the postglacial epoch.
igneous rock: a rock formed by the solidification of molten magma, lava or airfall tephra (volcanic ash). May be intrusive (solidified slowly from magma below the land surface) or extrusive (solidified from lava or tephra at the surface). Visible crystals indicate slow cooling below the land surface, often at depths of many kilometers.
illuvial clay: in a soil profile, clay that has been washed downward by percolating water, often to a characteristic depth where it may form “clay skins” on rocks, a dense horizon in the soil, or an impenetrable clay hardpan.
inverse: opposite to that which is usual. Specifically, unifacial retouch displayed on the margin of the ventral surface. Hence, the impact of percussion blows (or pressure) removing flakes is on the edge of the dorsal surface.
jasper: impure, opaque to slightly translucent cryptocrystalline quartz; a hard, fine-grained siliceous material, often black, green, or red in color.
keeled scrapers: unifacial scrapers having a ridged dorsal surface and a flat ventral surface
knapping: striking sharply; flaking; fashioning a tool from rock by percussion.
knapping station: a lithic workshop; an area of concentrated debitage or workshop debris where stone tools are produced.
lateral: the edge of a flake or tool. Frequently there are two laterals.
lenticular: lens-shaped; slightly convex on one or both sides; usually feathering out to sharp edges on the circumference.
lithic: pertaining to rock or stone.
lithic industry: an assemblage of stone (lithic) artifacts. A more limited term than “culture,” which implies a variety of evidence, including pottery and basketry.
lithology: intrinsic rock characteristics including chemical and physical compositions.
metamorphic rock: rock altered from its initial state by extreme heat and/or pressure. May show internal deformation or recrystallization by segregation of minerals in visible bands with distorted forms.
morphology: attributes of the form, type, and character of objects.
mudflows: viscous streams of mud washed from steep mountain slopes by high-intensity rains in areas of weak vegetative cover. The mud may transport small rocks and its viscosity allows it to float sizeable boulders far out onto alluvial fans. Distinct from a debris flow, which has a higher proportion of coarse rock material and is less free-flowing.
multiple scrapers: artifacts having more than one scraping edge, possibly of differing morphologies (straight, convex, concave, denticulate, pointed).
neotectonism: recent tectonic deformation (doming, folding, faulting); usually postglacial, or within the past 10,000 years.
notched: a narrow, purposefully-created indentation as on a notched scraper. In the present study, a notch encompasses less than one third of the edge of the specimen in which it occurs.
obsidian: black volcanic glass resulting from very rapid cooling of lava that solidifies before mineral crystals can form. Ideal material for sharp-edged blades. Not found in Calico pits though sources are nearby and were utilized by post-Lake Manix Native Americans.
ovate: egg-shaped in form, but not necessarily to as great an extent in cross-section as in length.
oxygen-isotope stage: chronological term derived from measurements of oxygen isotopes in marine microfossils. Oscillations in marine oxygen isotopes were produced by Quaternary sea level oscillations. Times of low sea level (glacial stages) left the seas enriched in the heavier isotope of oxygen, which is recorded in marine organisms. Glacial stages (low sea level) have even numbers; non-glacial stages have odd numbers.
Paleo-Indian: earliest Native American culture commonly recognized; characterized by diverse atlatl points, grinding stones, etc. Sites date from c.20,000 to c.5,000 BP., more commonly from c.12.000 to c.5,000 BP.
paleosol: a soil formed under conditions that no longer prevail; found either at the surface or buried under later deposits.
parent rock: in situ source of material utilized for lithic artifacts; may be a natural outcrop from which artifact raw material has been transported by geologic processes.
pebble: a rock fragment, commonly rounded to some degree, from 2 to 64 mm in diameter.
pedogenic: relating to soil-forming processes.
percussion flaking: removing flakes by striking a rock source with sharp controlled blows with a hard hammerstone or a soft hammer of bone, antler, or wood.
perforator: a sharply-pointed splinter-like tool used to pierce material such as wood or hide; may be a toothlike projection from an otherwise regular flake.
plano-convex: a flat ventral surface and an outwardly-curved (convex, domed, ridged) dorsal surface. (compare with concavo-convex)
platform: the area on a core, block, or thick flake where percussion impact falls, causing a new flake to be detached. The platform may be a natural surface, or it may be prepared in advance.
platform angle: on a flake, the angle formed by the intersection of the planes of the striking platform and the dorsal surface of the flake.
platform preparation: primary preparation is the removal of cortex from the proposed impact area. Subsequently, the platform area is retouched as desired.
Pleistocene: the “Ice Age;” the earlier of two epochs comprising the Quaternary; characterized by repeated glacial advances and recessions beginning about 1.8 million years ago and ending 8,000-10,000 years ago. Periods of glacial expansion at higher latitudes and in mountain areas were “pluvial” periods of increased rainfall and decreased evaporation in the Southwestern deserts of the United States, as shown by the evidence of large systems of lakes (now extinct) and radical vegetation change revealed by pollen analysis.
polygenetic: found under changing conditions; i.e., different climates.
preform: unfinished and unused form of an artifact, larger and less refined than the intended tool and roughed out crudely by direct percussion. An early stage of modification of a blank.
pressure flaking: removal of flakes from the dorsal or ventral edge of a rock specimen by pressure exerted by a hand-held tool made of bone or antler.
projectile points: piercing points of arrows and spears propelled through the air by hand, bow, or atlatl. Not present in Manix and Calico lithic industries.
provenance: the geologic setting or parent rock from which sediments or specific lithologies are derived.
provenience: the exact vertical and horizontal position of a specimen within an archaeological excavation.
proximal: the end of a flake or core that receives the flake-separating impact or pressure; normally the thicker end of a flake, that preserves the striking platform.
quarry: exposed source of desirable rock for tool fabrication; material removed by excavation, shattering, battering, or prying. Not a loose surface source such as float material naturally detached from the parent rock.
Quaternary: the geological period extending from the beginning of the Ice Ages, some 1.8 million years ago, to the present, composed of the Pleistocene and Holocene epochs.
Rancholabrean: faunal assemblage characteristic of the Late Pleistocene “Ice Age” in North America. Marked by the addition of bison to the association of mammoth, mastadon, camel, horse, and their predators. Extending from about 500,000 to 10,000 B.P.
reamer: a tool used with a rotating motion to enlarge a hole in wood or hide. The distal portion of the reamer shaft may show retouch.
rejects: modified but unfinished lithic artifacts.
relict soil: an identifiable soil not formed by current soil-forming processes; may be at the surface or buried by more recent deposits and soils.
removal scar: scar on a core or flake resulting from detachment of a flake or chip; usually, but not universally, a concavity.
retouch: detailed modification of a lithic artifact by percussion or pressure flaking. Primarily used with reference to the shaping of the edge of a tool. May also relate to surface removal scars, i.e., face flaking or surface retouch.
rhyolite: silica-rich extrusive igneous rock derived from viscous chemically-acidic lava. Low in density and light in color, ranging from gray to pink or yellow. Rhyolitic tephra (ash) forms extensive beds of the rock known as tuff.
ripples: see compression rings
rock varnish: film of clay minerals and metallic oxides that form on rocks in many environments. “Desert varnish” conventionally refers to black manganese-rich films on rock exposures in deserts, including desert pavements. The undersides of desert pavement rocks reveal an orange stain of iron oxide. If the orange side of a pavement rock is visible, one knows that the rock has been overturned subsequent to varnish formation.
rotational tools: tools such as drills, augers, reamers, used with a twisting or rotating motion to open or enlarge holes.
siliceous: of or pertaining to silica (SiO2); containing abundant silica; a very hard naturally occurring mineral that is ideal for lithic artifacts. Siliceous chert, flint, and chalcedony take and hold sharp, durable edges.
soft hammer: hammer of antler, bone, or wood, used in flaking.
spall: an element of debitage; i.e., a waste product; usually detached in the preparation of a burin in which the knapper’s blow is delivered to the transverse cutting edge. Spalls are usually long, narrow, and columnar.
step flake: a flake scar that terminates abruptly in a right angle.
stockpile: a storage pile, usually on the surface. At Calico it is a storage pile with provenience labeling of apparently non-diagnostic material retained for future analysis.
technical flake: a diagnostic percussion or pressure flake having definite attributes relative to knapping technology.
tephra: volcanic ash. (See tuff)
thermoluminescence: emission of light by material that has absorbed energy from radioisotopes in its enclosing matrix; thermoluminescence (TL) dating is a complex laboratory procedure that measures the intensity of such light and converts this to the time of burial of the object or sample in question.
torqued: twisted in relation to the normal long axis; a product of force.
tortoise scrapers: scrapers with a strongly domed dorsal surface meeting a flat ventral surface in a sharp edge; common, though use is uncertain.
triangulation: the measurement of distance from three established points to fix the location of an object. In the Calico excavations the three points are the unit’s northeast and northwest corners for horizontal position, and the unit’s datum point for vertical position.
tufa: a chemical deposit or sedimentary rock composed of calcium carbonate or silica precipitated from solution in a body of water, or by ground water.
tuff: lithified fine-grained volcanic tephra. A chronological marker as its age may be determined radiometrically by potassium/argon (K/Ar) analysis of several included minerals.
uranium-series dating: age determination of materials by the decay of included unstable uranium isotopes to more stable isotopes of thorium. Especially useful in dating carbonates such as cavern deposits and soil K horizons.
uniface: flaked only on one face or one side of an edge. Refers to face flaking, edge retouch, and use wear.
ventral: the lower or under surface; also the inner surface. Opposite to the outer (dorsal) surface or face.
vesicular horizon: silty vesicle-rich layer underlying desert pavement rocks. The silt is trapped by the pavement during dust storms and the silty layer increases in thickness through time.
witness column: a columnar block of the total deposit left intact near the center of a large excavation as representative of the material removed.