A list of simple definitions for terms used by southern California archaeologists

Abrader – A groundstone tool with abraded/ground edge, typically used for scraping, such as to process agave leaves into fibers that can be used to make twine.

Acorn – Acorns are the fruit of the oak tree. Many Native Americans used “Acorns” for food. Acorns have to be ground into meal and then leached by running water through the meal to remove poisonous tannic acids prior to consumption.

Adobe – A Spanish term meaning “mud brick or block.” It is a sun-dried, unfired brick or building block made from a mixture of clay, straw, and water. The term can also refer to the clay or soil from which the brick is made, or a structure built with this type of brick.

Agave – This plant has fleshy, toothed leaves and was harvested for both food and fiber. The fibers were twisted into twine or cords that were used as string or rope or woven into nets (see Carrying Net below). The entire plant was dug up and roasted in an earthen oven and eaten much like a giant artichoke.

American Period – In California, the American Period is from the annexation of California in 1848 to the present. Also see Spanish Period, Mexican Period, and Mission Period below.

Anvil Stone – A larger base stone used to hold something that was pounded or hammered. It usually shows evidence of pounding (pitting, battering, etc.) on its surface.

Archaeological Record – This term is used to refer to things recovered or recorded through the process of doing archaeology (see below).

Archaeology/Archeology – The study of the material culture and remains of past human life and activities. In California it is often divided into “Prehistoric Archaeology” (the time period before the Europeans arrived in this region – see below) and “Historic Archaeology” (the time period after Europeans came to the region – see below).

Archaeologist – one who studies archaeology (see above). Most professional archaeologists have a college degree in the field of archaeology and work for either a CRM firm (see below), a public agency (city, county, state or federal agencies such as parks, highway departments, forestry and fire departments, military bases, etc.), a college/university, or a museum. Avocational archaeologists are those who do not have a college degree in the field but are interested in archaeology, do volunteer work or pay for the opportunity to work under the guidance of professional archaeologists, and/or belong to an archaeological society such as the San Diego County Archaeological Society.

Arrowhead – When most people hear the term “Arrowheads” they think of small triangular points made out of stone. Archaeologists call them “projectile points” (see below).

Artifact – An artifact is an item made or used by humans in the past. In California, archaeological artifacts include both historic and Native American items that are more than 50 years old.

Asphaltum – “Asphaltum” is a naturally occurring tar that the Native Americans used as an adhesive and a coating to waterproof baskets and boats.

Atlatl – An atlatl or “spear thrower” is a tool used to throw or fling a dart shaft. The long shaft of the atlatl acts as an arm extension and results in a more powerful throw than the human arm alone could accomplish. Atlatls were generally used in southern California prior to the Bow and Arrow (see below). Although atlatls were typically made out of wood and do not usually survive, stone atlatl weights and stone dart points have been identified and can be used to date a site.

Auger – Archaeologists use augers to test for the presence or absence of buried archaeological sites. A hand auger consists of a long pole with handles on one end and a narrow bucket on the other end with cutting blades on the bottom. It is turned like a drill to cut into and bring up dirt, which the archaeologist then sifts through to see if any artifacts or other cultural items are present. Mechanical augers are often mounted on the back of a truck, shaped like a giant drill bit, and turned by a motor. (Also see “STP” below.)

Awl – This pointed tool resembles a large needle and was usually made of bone. Awls were often used in basket making. Also called “Bone Awl” or “Basket Awl”.

Bark Skirt – Traditional clothing of many southern Californian Native Americans. Made out of long strips of bark that were pounded to soften them then tied with agave fiber twine or leather strips around the waist.

Basin – A shallow bowl-shaped depression in a bedrock outcrop that has been made and/or used for grinding foodstuffs or other materials (see Groundstone below). A certain type of basin found in San Diego County mountains is known as a “Cuyamaca Oval” for its elongated oval shape. Compare to “Metate”, “Mortar”, and “Slick” below.

Basket – Native Americans used baskets for storage, collecting, cooking, and as hats. They were typically made of certain pliable plant fibers such as bunch-grasses, juncus reeds, basket bush, and willow. The most common type of baskets in southern California were coil baskets.

Bead – Native Americans typically made beads out of stone, shell, and bone by breaking these materials into small, thin fragments, drilling holes in the center, and then grinding down the edges to make them round or square. Beads were used as decorations on pottery, baskets, and other objects, for jewelry, and for trade.

Biface – “Biface” is a term archaeologists use for stone tools that are worked on two sides to make a sharpened edge. Knives, arrow points, and scraping tools are often bifaces.

Bow and Arrow – The smaller bow and arrow was a technological advancement over the dart and atlatl. In southern California, bows and arrows started to be used around 1,500 years ago.

Breaker Bar – A breaker bar is a tool that archaeologists use during excavations. It is a heavy, solid metal rod with a sharp end used for breaking up hard soil.

Cahuilla – The “Cahuilla” are a tribe of Native Americans who live in the southern California mountains and deserts. Their territory extends from Riverside County into northern San Diego County.

Carrying Net/Net Bag – Native Americans used these open-weave bags for holding and transporting many items. They were typically made out of agave fiber that was twisted into twine and then knotted into net-like bags.

CEQA – CEQA (pronounced “see-kwah”) stands for the “California Environmental Quality Act”, which was signed into law in 1970. It requires developers and others to identify the effects a project might have to the environment and various resources, including archaeological sites, and to avoid or mitigate (see “mitigation” below) significant effects to those resources. Also see “NHPA” and “Section 106” below.

Chert – “Chert” is a type of stone that was used for making tools. It was highly prized because it is easy to work with, holds a sharp edge, is more durable than obsidian, and comes in a variety of colors.

Chumash – The “Chumash” are a group of Native Americans whose ancestors lived in San Luis Obispo County, the Santa Barbara Channel area including mainland Santa Barbara County and the northern Channel Islands, and in Ventura and northern Los Angeles counties. The name Chumash is a derivation of the name that the mainland Chumash called the inhabitants of Santa Cruz Island but it has come to be used for all the linguistically-related Native Americans of the central and southern California coastal areas.

Clay – This naturally occurring substance is malleable when wet and stone-hard when fired. It was used for making pottery containers, tools, and other objects such as pipes, gaming pieces, effigies, and ornaments.

Collection – A group of artifacts (see above), cultural constituents (see below), and associated information (such as catalogs, reports, field notes, photographs, etc.) from an archaeological site or project.

Compass – A compass is a tool used by archaeologists for navigating and determining directions. Also see “GPS” (below).

Conchoidal Fracture – This term refers to a curved breakage in stone or other hard substance that resembles concentric ripples emanating out from the point of impact. Also see “Flake Scars” (below).

Core – A “Core” is a piece of stone from which three or more other pieces of stone were removed to make tools. You can tell how many pieces were removed by counting the “Flake Scars” (see below).

Core Tool – A core tool is a core (see above) that was formed into a tool. Larger scrapers, choppers, and other bigger tools are often core tools.

CRM – CRM stands for “Cultural Resource Management” and it is a term used to describe project-driven archaeology, such as that done for environmental compliance (see “CEQA” above and “NHPA” and “Section 106” below). It is also called “salvage archaeology” or “compliance archaeology”.

Cultural Constituents – Items from a site or collection that are not artifacts (see above) but indicate cultural use such as human teeth and bone, animal bone and shell food remains, and unmodified materials that do not naturally occur at the site.

Cultural Resource – “Cultural Resources” include archaeological, ethnographical, traditional, and historical sites, as well as artifacts, features, landscapes, properties, and built-environment resources including but not necessarily limited to buildings, structures, objects, and districts.

Cupeño – The Cupeño are a small tribe that lives in the northern San Diego County mountains.

Cupule – A small pecked or ground, shallow hole in a rock or outcrop. Cupules are often considered to be non-utilitarian forms of rock art especially when they occur on non-horizontal surfaces. There are similarly-sized and shaped grinding holes that may have been used for processing specialty foods or other resources, or as a form of mineral extraction.

Curate – To organize, store, and maintain a collection (see above) or individual artifacts. See “Curation Facility” below.

Curation Facility – A Curation Facility (or “Repository” – see below) is a building specifically designed to curate collections. The San Diego Archaeological Center is the curation facility for San Diego County. Please see their website ( for more details.

Datum – A “Datum” is a specific point that is used to reference a site or a unit. Measurements from a site datum to various artifacts and features are taken to create a map of the site. Measurements of the depth of artifacts and features found in situ (see below) while excavating a unit are taken from a unit datum (the highest corner of a unit).

Debitage – “Debitage” is a word used to describe waste material from “knapping” (see below). Archaeologists use this term to refer to unmodified/unused “flakes” (see below), broken flakes, and angular stone fragments with no flake characteristics.

Emic – Of or relating to features or items analyzed with respect to their role as structural units in a system, as in behavioral science or linguistics.

Etic – Of or relating to features or items analyzed without considering their role as a structural unit in a system, as in behavioral science or linguistics.

Ethnography – is the scientific description of individual human societies. Ethnographic information is gathered first hand through interviews with and observations of persons living in a specific cultural group.

FAR – “FAR” stands for “Fire-Affected Rock” or “Fire-Altered Rock”. Rocks that have been exposed to hot, long-burning fires undergo a chemical change that alters their color and can make them more brittle. FAR often turn red, black, or grey depending on their composition, the length of exposure to fire, and the temperature of the fire. Another term that is sometimes used is FCR or “Fire-Cracked Rock”

Feature – A feature is immovable evidence of a human activity occurring in a specific location. Features can be made up of groupings of artifacts such as a “pot drop” or a “flaking station”; bedrock uses such as bedrock grinding (e.g., mortars, slicks, basins), rock art (pictographs, petroglyphs), or rock shelters; or use areas such as fire pits/hearths, rock enclosures, quarries, or trails.

Flagging tape – brightly colored flagging tape made of plastic, paper, or fabric is used by archaeologists for marking artifacts and features in the field. Compare to Pin Flag (see below).

Flake – A flake is a small fragment of stone that shows certain characteristics indicating it was intentionally broken off (flaked off) a larger stone (see “core” above). Some of the characteristics of a flake include a “bulb of percussion,” a “striking platform,” and a thin triangular cross-section. Also see “Debitage” above and “Flaked / Chipped / Knapped Stone” below.

Flaked / Chipped / Knapped Stone – An archaeological term that refers to stone tools made by flaking, chipping, or “knapping” (see below) stone materials to create a sharp edge. See and “Core Tool” and “Flake” above and “Flake Tool”, “Projectile Point”, and “Retouched Flake” below.

Flake Tool – A tool made out of a flake. Smaller-sized cutting, scraping, and drilling tools are usually made from flakes.

Flaking Station – A flaking station is also called a “Lithic Reduction Station” or LRS (see below). It is a grouping of debitage of the same material, coming from the same “core” (see above)

Flake Scar – This term refers to the depression left when a “Flake” (see above) is removed from a rock. Some of the characteristics used to identify a flake can also be seen in reverse within flake scars.

Field – When an archaeologist says he or she is going out in the field, that means going outside to a site or an area where there are or may be sites. Another term archaeologists use is “Fieldwork” which just means working outdoors instead of in the office or lab.

Geoglyph – A picture or symbol formed with rocks, trails, or other earth modifications across a landscape. The most famous geoglyphs are the Nazca Lines in Peru, but there are also a number of Geoglyphs in the southern California deserts.

GIS – Geographic Information Systems (GIS) are computer systems used for capturing, storing, checking, integrating, manipulating, analyzing, and displaying data related to positions on the earth’s surface. Archaeologists use these systems to work with spatial data relating to archaeological sites.

GPR – “GPR” is an abbreviation for Ground Penetrating Radar, a technology used by archaeologists to help find buried features and sites.

GPS – “GPS” is an abbreviation for “Global Positioning System” which is used by archaeologists for navigating to and recording/mapping sites, features, and artifacts.

Grid – Archaeologists use a grid to divide an archaeological site into small squares that make it easier to document surface distribution of artifacts and plan out testing and excavation.

Groundstone – An archaeological term that refers to stone tools and bedrock features that were used to grind or process seeds, pigments, clay, fibers, or other food or materials. Also called millingstones (see below). Groundstone tools include manos (see below), pestles (see below), and portable metates (see below) and mortars (see below).

Groundstone Feature – Groundstone features include bedrock slicks (see “slicks” below), basins (see above), and mortars (see below). Also called “Bedrock Grinding Features” or “Bedrock Milling Features.”

Hammerstone – “Hammerstones” are rocks used to make stone tools by hammering on cores (see “Core” above). You can tell a rock was used as a hammer due to crushing or battering evident on its edges or surface.

Historic Archaeology – The study of the material culture of historic period peoples. In California the historic period begins with the arrival of the European settlers and missionaries. Compare “Prehistoric Archaeology” below. Also see “Protohistoric” below.

Information Center – Information Centers or “Info Centers” are repositories (storage facilities) for paper records including “Site Records” (see below), maps, and reports that relate to archaeological and historical sites and resources. Most Information Centers are responsible for records for two or more counties. Information Centers are part of the California Historical Resources Information System (CHRIS) overseen by the Office of Historic Preservation (see OHP below). The information center for San Diego and Imperial counties is the South Coastal Information Center.

In SituThis is a Latin term meaning “in the position” and means an object is in its original location. Archaeologists use this term to indicate the location where an artifact was originally deposited. A similar term that is also used is “in context.” The context or surroundings of an artifact and its relationship to other artifacts or features within a site can tell an archaeologist as much or sometimes even more than the artifact itself can. This is why it is important to leave artifacts in place until they can be examined and recorded in situ or recovered using scientific processes to document the surroundings of the artifact.

Isolate / Isolated Artifact – An isolate is one or two distinct artifacts (see above) or a few fragments of the same artifact that are too far away (typically more than 30-50 meters) from other artifacts or features (see above) to be considered part of a site (see below).

Juncus – These bunching grass-like plants with long stems grow in wet areas. They were used for making baskets.

Kamia – The “Kamia” are a group of Native Americans that live in the eastern mountain and desert regions of San Diego County.

Knapping – Knapping is the controlled breaking up and shaping of rocks to make stone tools. Also called “Flint Knapping.” A stone worked using this process is said to have been “knapped” (also see under “Flaked / Chipped / Knapped stone” above).

Kumeyaay – The “Kumeyaay” are a group of Native Americans who live in San Diego County. The Spaniards gave them the name “Diegueño” due to their proximity to the Mission San Diego de Alcalá.

Level – An archaeological excavation level is a portion of a “Unit” (see below) that is removed and processed at one time and as one group. Levels can follow strata in the soil (“Stratigraphic Levels”), but more often in southern California, levels are 10 centimeters thick and are either dug parallel to the horizon (“Horizontal Levels”) using a “line level” (see below) or parallel to the ground surface (“Arbitrary Levels”).

Line Level – A leveling tool that attaches to a string or line. Archaeologists use line levels to dig Horizontal Levels (see under “Level” above) in units (see below) and to measure the depth of artifacts or features in a unit from a unit datum (see under Datum above).

Lithic – This term means “stone”, therefore a “lithic tool” is the same as a stone tool.

Lithic Procurement Area – This term is used to refer to an area where certain types of stone were gathered or collected for tool making purposes. Typically the stones were knapped (see “Knapping” above), partially knapped, or tested (see “Test Cobbles” below) leaving debitage (see), hammerstones (see), and/or cores (see) behind.

LRS – “LRS” stands for “Lithic Reduction Station,” also called a “Flaking Station” (see above). It is a small area where there are flakes or debitage from the same stone, indicating someone was standing or sitting in that location and “Knapping” (see above) to make stone tools.

Luiseño – the Luiseño are a tribe of Native Americans living in northern San Diego County and western Riverside County. Their ancestors were given the name “Luiseño” due to their proximity to the Mission San Luis Rey de Francia. They call themselves Payomkawichum, a name that means “Western People”.

Mano – “Mano” is a Spanish term meaning “hand.” Archaeologists use the term “Mano” or “Handstone” to refer to a stone tool used to grind nuts, seeds, clay, or other materials (also see “Metate”). It is typically flattened on one or two faces from grinding use and fits easily into the hand. It is used in a circular or back and forth motion. Also see “Groundstone” above.

Map – Archaeologists use maps for navigating and finding known sites and locations, as well as for plotting site locations. Historic maps can provide information on what once existed in a location and can sometimes lead to the identification of historic sites.

Metate – A “Metate” is a large flat rock used as a base-stone for grinding various substances (see “Mano” and “Groundstone” above). Portable metates are often shaped into rounded forms, but can simply be unshaped slabs of stone. Bedrock metates are usually called “slicks” (see below) or “basins” (see above) depending on how much of a depression has been formed.

Mexican Period – In California, this period lasts from Mexico’s independence from Spain in 1821 to the annexation of California by the United States in 1848.

Microfloral Analysis – this study is done to determine the presence of microscopic plant fragments or seeds within an archaeological sample. It is usually used on soils within a feature such as a hearth or a mortar to determine what types of plants were being used or processed.

Midden – A deposit containing ancient refuse (trash) such as shell, bone, and other organic materials. Midden soils are often dark due to these decomposed organic materials (similar to what you might find in modern compost soils) and may feel greasy or ashy. Some shell middens are made up almost exclusively of shellfish remains and contain very little soil or other organics.

Millingstone – The term Millingstone originally was used to refer to stone tools used for grinding, such as Manos and Metates, however, because these tools are often used for more than “milling” grains, the term Groundstone (or ground stone) is often preferred (see above).

“Millingstone” is also the name of a time period dating from between approximately 9,000 and 5,000 years before present. It is characterized by the presence of abundant manos and metates (see above).

Mission Period – In California, the “Mission Period” lasted from the founding of the first Alta California mission in San Diego in 1769 to secularization of the mission system in 1833. The Mission Period includes the Spanish Period (see below) and the Mexican Period (see above). Also see American Period (above).

Mitigation – “Mitigations” or “mitigation measures” are treatments proposed under environmental review (see CEQA, NHPA, and Section 106) that are meant to reduce the severity or significance of a project’s effects or impacts to a resource (including archaeological sites). Archaeological excavation or “data recovery” is one type of mitigation often used to recover data about an archaeological site before it is damaged or destroyed by development (see CRM above).

Mortar – A shallow to deep, circular hole or depression in a bedrock outcrop that is used as a container for pounding, pulverizing, and/or grinding acorns, seeds, plants, pigments, or other materials and foods with the use of a pestle (see below). Portable mortars that are shaped on the outside are often classified as stone bowls.

NAGPRA – NAGPRA is the “Native American Graves Protection and Repatriation Act”. It was enacted in 1990 to address the rights of lineal descendants, Indian tribes, and Native Hawaiian organizations to repatriate (see below) and recover Native American cultural items, including human remains, funerary objects, sacred objects, and objects of cultural patrimony from museums, curation facilities, and other institutions.

National Register – The National Register of Historic Places (also called the National Register or NRHP) is the Nation’s official list of significant cultural resources worthy of preservation. Authorized under the National Historic Preservation Act (see NHPA below), the National Register is part of a national program to coordinate and support public and private efforts to identify, evaluate, and protect our historic and archeological resources.

NHPA – NHPA is the “National Historic Preservation Act”. It was passed in 1966 and supports historic preservation activities and programs. It established the National Register of Historic Places (see above), the SHPOs (see below), and “Section 106” (see below).

North Arrow – Usually made from a piece of wood, plastic, or metal with a printed or painted photo scale (see below) and a point on one end. Archaeologists use “North Arrows” for indicating which direction is north when they take photographs of sites, features, units, or artifacts.

Obsidian – This natural volcanic glass was highly prized as a material for making stone tools. It is very easy to work and provides an extremely sharp edge, but it is brittle, so it often does not survive much use. Obsidian has distinct mineral characteristics that can be used to identify or “source” the origins of obsidian found at archaeological sites. In southern California the closest source of obsidian was at Obsidian Butte out by the Salton Sea, but other sources exist farther north in central and northern California and south in Mexico. By determining where obsidian found in an archaeological site came from, archaeologists can determine trading patterns. Also see “Obsidian Hydration” below.

Obsidian Hydration – A technique used to determine the relative date of a site. When it is broken, knapped, or flaked, obsidian (see above) starts to form a microscopic rind that grows at a specific rate depending on the moisture, exposure, and soil conditions. This rind can be measured and used to determine how long ago the stone was worked.

OHP – In California, the SHPO (see below) heads the California State Office of Historic Preservation (OHP), which is responsible for identifying, evaluating, and registering historic properties, for ensuring compliance with federal and state regulatory obligations, and for promoting historic preservation. The OHP also maintains the statewide Historical Resources Inventory database managed by the California Historical Resources Information System (CHRIS), which oversees the regional Information Centers (see above)

Olla – This is a Spanish term for an open-mouthed clay pot, often used for cooking or storage (also see “Potsherds” below)

Pestle – An elongated and cylindrical stone that are sometimes shaped to fit into a mortar hole. It shows battering or pounding on one or both ends and sometimes grinding around the edges. It is used with a mortar (see above) to crush, pound, pulverize, or grind seeds, plants, pigments, or other materials and foods.

Petroglyph – a form of rock art that is carved, scratched, pecked, or ground into a rock surface. Compare to pictograph (see below).

Pictograph – a form of rock art that is painted onto a typically vertical rock surface using natural or mineral pigments. Compare to petroglyphs (see above)

Pin flag – A long piece of sturdy wire with a small, brightly colored flag on one end, used by archaeologists for marking artifacts and features during recordation of a site.

Photo Scale – archaeologists use a photo scale for showing the size of artifacts, features, or excavations in photographs. Historic archaeology typically uses scales showing inches or tenths of a foot, while Prehistoric archaeology uses metric scales with centimeters.

Pot Drop – This term is used to refer to a small grouping of “potsherds” (see below) that fit together, or are all from the same pot or pottery vessel. A “Pot Drop” is an archaeological “feature” (see above) indicating that a pottery vessel was dropped and/or broken at this location.

Potsherd – Archaeologists seldom find whole pots or pottery vessels, instead they usually work with broken fragments called “Potsherds” or “sherds” (see below). Sometimes archaeologists can piece a vessel back together if they can locate all of the potsherds. Potsherds often bear certain characteristics that can provide information about what type of vessel it came from and how that vessel may have been used. “Rim sherds” include the lip of the vessel. “Decorated potsherds” include those with incised designs or painted-on pigments. “Slipped potsherds” had a thin layer of white or pale clay painted on the outside as a decorative element. “Drilled potsherds” contain a small hole that was drilled after the pot was fired in order to repair broken vessels by tying pieces together with twine. Some potsherds were also ground down around the edges and used as pendants or as game pieces.

Prehistoric Archaeology – In California, Prehistoric Archaeology is the study of the material culture of Native Americans from the time periods before they adopted or had a European lifestyle imposed upon them. Compare with “Historic Archaeology” above. Also see “Protohistoric” below.

Primary Number – a primary number is assigned to an archaeological site, historic building, or isolated artifact much like a “Site Number” (see below) is assigned. Primary Numbers are also assigned by the Information Centers and include a numeric ID for the county in which they were identified as well as a sequential number assigned to the particular site, building, or isolate. Archaeological sites are assigned primary numbers as well as trinomials (see under Site Number below).

Projectile Point – This term is what archaeologist use for stone points that were attached to long, straight sticks to make darts or arrows and used with atlatls or bows respectively. Most non-archaeologists call these “arrowheads.” There are many varieties and they evolved over time. Archaeologists can often date a site based on the type and style of projectile points found there.

Protein Residue Analysis – this type of study looks at proteins left behind by plants and animals using an immunologically-based technique. These analyses can show if a stone tool was used to cut, scrape, or grind a certain plant or animal species.

Protohistoric – This term is used to describe the time period between the arrival of European explorers and trade items in California and the adoption of basic European lifestyles by the Native Americans of the region. For example, protohistoric archaeological sites contain mostly traditional artifacts and features with an occasional glass bead, metal tool, ivory button, etc. or traditional tools made out of European materials such as bottle glass or porcelain projectile points.

Provenience – The source or origin of an object. In archaeology this refers to the specific place within an archaeological site where an artifact or item was originally located. An item’s placement in a site provides information about what was occurring at that location and the relationship to other artifacts and features within the site area. This is an important part of the story of an archaeological site, and why it is important not to move or remove artifacts from a site without completing archaeological studies and documentation.

Quarry / Stone Quarry – Prehistoric quarries are locations where naturally occurring outcrops or deposits of certain types of stone were broken up and/or removed, typically for making stone tools. Compare to Lithic Procurement Area (see above). Historic quarries can include locations where rock or sand was removed for use as building materials, etc.

Repatriate – To restore or return to original or native land. In archaeology this term is usually applied to human remains, burial items, and sacred objects being returned to the Tribe or group of native peoples from which it originated. The act of returning such items is called “repatriation.”

Repository – A curation facility (see above) for storing, maintaining, and managing collections.

Retouched Flake – A “retouched flake” is a flake (see above) that has been purposefully worked along an edge to create a simple tool. It is a type of Flake Tool (see above).

Rock Art – This term refers to any design or image placed on a rock face or boulder that does not have a utilitarian purpose. Types of rock art include petroglyphs (see above), cupules (see above), and pictographs (see above).

Screen – An archaeological screen is a frame made of wood or plastic containing a sheet of wire mesh on the bottom, typically with holes of either 1/16-, 1/8-, or 1/4-inch. It is usually mounted to collapsible legs, attached to a motorized shaker-frame, or fitted to hang from a larger frame. Archaeologists use “Screens” to sift through excavated dirt to find artifacts by shaking the screen or pushing/scraping the dirt through the wire mesh using trowels or hands. This process is called “Screening”. Also see waterscreening below.

Section 106 – “Section 106” is part of NHPA (see above) which requires all federal projects or state, local, or private projects with federal involvement (e.g., funding, permits, lands, etc.) to identify and assess the project’s impacts to archaeological sites.

Shard – The term “shard” refers to fragments of glass (compare to “Sherd” below).

Shell / Shellfish Remains – The Native Americans along the coast collected shellfish for consumption from the beaches, bays, and ocean. The shells left over when they removed and ate the meat inside can tell us about what the Native Americans were eating, what time of year they were at the coast, how many people lived or stayed in an area, and even information about climate or harvesting procedures. These leftover shells were also used as tools including bowls and spoons, or modified to make ornaments such as beads (see above) or pendants, as well as to make tools such as fishhooks. Also see “Midden” above.

Sherd – The term “sherd” refers to pottery or ceramic fragments (compare to “Shard”). Also see “potsherd” above.

Shovel – Archaeologists use shovels to find and recover buried artifacts. Straight-nosed shovels are for digging straight walls and square pits, round-nosed shovels are for moving dirt and digging round test holes or STPs (see below).

SHPO – The SHPO (pronounced “ship-oh”) is the “State Historic Preservation Officer”. In California, the SHPO heads the California State Office of Historic Preservation (see OHP above). Many Native American tribes also have historic preservation officers called Tribal Historic Preservation Officers or THPOs (pronounced “tip-oh”).

Site / Archaeological Site – Archaeological “Sites” are specific places where there are artifacts or features indicating some human activity occurred at that location. In southern California a typical definition of a site is one or more “features” (see above) and/or a scatter of at least three distinct “artifacts” (see above) within 50 meters of each other. Compare to “Isolate” (see above).

Site Number / Site Trinomial / Trinomial – Site numbers are assigned to sites in the order they are recorded with the state Information Centers (see above). The Site Trinomial system for numbering archaeological sites was developed by the Smithsonian Institution and uses three numbers: a number ID for the state where the site is located, a number for the County in which the site is located, and a sequential number assigned to a site in the order it was recorded by the Information Centers. In California, instead of using the state number (4) and the county numbers, letter codes are used for the state and county: CA (for the state), and a three-letter code for each county (e.g., SDI stands for San Diego County, IMP stands for Imperial County, LAN stands for Los Angeles County). So the site trinomial CA-LAN-1 indicates the first site recorded under the trinomial system in Los Angeles County, California, whereas CA-SDI-20156 is the 20,156th site recorded in San Diego County, California. Also see “Primary Number” above.

Site Record / Site Form – Site records are official documents used for identifying and recording archaeological sites. In California, the official site record forms are put out by the Office of Historic Preservation’s California Historical Resources Information System (CHRIS). Once completed by archaeologists, these forms are stored in record storage facilities called Information Centers (see above).

Slick / Grinding Slick – A flat, horizontal area of a rock or outcrop that has been worn smooth by grinding or processing materials with a handstone or mano. Slicks have very little or no depth. Also see “metate” and “groundstone” above.

Spanish Period – In California the Spanish Period is from the arrival of the first Spanish settlers and missionaries in the late 1700s to Mexican Independence from Spain in 1821. The “Mission Period” (1769-1833) overlaps much of the Spanish Period.

Stratum (singular) / Strata (plural) – Layers of soil distinguished by color or compositional changes.

Stratigraphy – The arrangement of the strata (see above) within an archaeological site that shows the relative positions of artifacts, features, and cultural constituents and therefore the chronology of successive levels of occupation.

STP – “STP” stands for “Shovel Test Pit” a small shovel-dug hole used to determine presence or absence of subsurface archaeological materials in an area where sites are suspected. Compare to “Auger” and “Unit”.

Tape measure – Archaeologists use tape measures for determining depth and width of units or other excavations, and measuring the size of sites, features, and artifacts.

Test Cobble – This is a term used to refer to a rock that has only one or two “Flake Scars” (see above) on it. Compare to “Core” (see above).

Tinaja – Spanish for “large earthen jar.” Also used to refer to a basin-shaped water catchment area usually carved into bedrock by natural erosion, although some are human-modified or enhanced.

Trowel – Archaeologists use small-bladed triangular- or square-nosed masons’ trowels to help them excavate and screen (see above).

Unit – The square pits that archaeologists dig are called “Units”. A typical size used in southern California is a 1×1-meter square excavated in 10-cm levels. These are often called “one-by-ones” in the field.

USGS Maps – The 7.5-minute maps, produced by the United States Geological Services (USGS), are the current standard in California for plotting archaeological site locations for inclusion in a site record (see above).

Utilized Flake – An unmodified “flake” (see above) with evidence of use such as micro-flake scars, use-wear, or polish (visible under a microscope).

Waterscreening – Waterscreening is similar to regular archaeological screening (see under “Screen” above). But instead of shaking or pushing the dry soil through the wire mesh, water is used to break up hard or clay soils and wash the dirt away from the artifacts and through the wire mesh. This method is typically used to recover more small pieces that may be hidden in dirt clods from site deposits with a potentially richer density of artifacts.

Whisk Broom – these tools are used by archaeologists for cleaning off dirt from features or unit floors. Archaeologists use plastic or synthetic fiber whisk brooms instead of those made from plant fibers to prevent contamination of protein residue, microfloral, or other specialized study samples.

Yucca – A native southern California plant with long, tough, pointed leaves that were harvested for fiber.


Special thanks to Marla Mealey for providing this glossary of archaeological terms.