Artifact of the Week: Pottery Sherds

Indigenous peoples of Southern California have been creating and pit-firing clay pottery for thousands of years. Prehistorically, two pottery wares were constructed in the region. The inhabitants of the peninsular mountains produced Tizon brown ware while people in the Colorado Desert created Colorado buff ware. Both were produced by the paddle-and-anvil technique and fired in low-temperature open pits. So why are they different colors? The local clay from which they are produced contains distinct amounts of minerals and water, thus creating the color variation.

Tizon Brown Ware

Archaeologists find this plain unglazed ware in the mountain and coastal regions of San Diego County. Tizon is medium brown with black “clouds” from firing. It has a coarse texture with shell, ground pottery, quartz, feldspar, or mica incorporated in the clay as temper. (Temper is material added to clay to reduce rapid shrinkage or expansion and to distribute heat more evenly during firing.)

Colorado Buff Ware (aka Desert Buff Ware)

Indigenous peoples made this pottery from clays found in former lake bottoms and alluvial desposits of the Coloroado River in Imperial County. It is cream-colored, unglazed buff with a with a pinkish cast. Thinner and harder than Tizon, buff ware includes gypsum (salts) which may give it a “scum” or dusty appearance.


To learn more about local pottery, visit the exhibit The Life Cycle of a Pot currently on view at the San Diego Archaeological Center.

Date: Late Prehistoric Period (3,000 – 300 Years Ago)
Material Class: Pottery – Tizon Brown Ware and Colorado Buff Ware

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With the assistance of Center staff, the intern will use photogrammetry to prepare one or more archaeological collections for digital preservation, as well as create a virtual museum exhibit for our Public Archaeology department. Per approval, special projects of the intern’s choosing are also available. During the research and planning, the intern will receive guidance as appropriate to their selected project. Prospective interns should already be familiar with photogrammetric procedures, and Agisoft Metashape.

Collections Management

With the assistance of Center staff, the intern will prepare one or more archaeological collections for curation. During the course of the internship, the intern will learn to identify artifacts and ecofacts common to the San Diego region, including lithics, ceramics, historical objects, and faunal, botanical, and mineral specimens. Center staff will instruct the intern on archaeological laboratory procedures such as basic artifact analysis, manual and computer cataloguing, storage requirements, and preventative conservation. In addition, the intern will become familiar with historical trends in archaeological practice in the San Diego area and will be introduced to current legal and ethical issues in archaeological curation as well as the concerns and rights of culturally affiliated groups with regard to archaeological materials.

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Geographical Information Systems in Archaeology

Prospective Interns must have completed three courses: Introduction to GIS, GIS Database Management, and Intermediate/Advanced Methods in GIS. The intern will be assigned a project where they will create shapefiles and maps for curated archaeological collections, museum exhibits, and/or public outreach using ArcGIS 10.6. Center staff will instruct the intern on archaeological GIS laboratory procedures such as computer cataloguing, storage requirements, and database management.

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With the assistance of Center staff, the intern will arrange and catalog materials in the Center’s library. During the course of the internship, the intern will take a leading role in the cataloging, sorting and storing of research files and creating user guides for these collections. Center staff will instruct the intern on archival procedures, computer cataloging, storage requirements, and preventative conservation.

Public Archaeology

Harness your passion for Public Archaeology and gain hands-on experience with K-12 museum field trips, lectures, and public outreach. Additional projects may include creating virtual museum exhibits and activities, assisting in the development and implementation of K-12 curricula programs, planning and presenting public facing content, or educational field trip content of your own design. Must be able to pass a Live Scan.