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North Dakota: Legendary. Follow the trail of legends

Backstage Pass to North Dakota History

This blog takes you behind the scenes of the State Historical Society of North Dakota. Get a glimpse at a day-in-the-life of the staff, volunteers, and partners who make it all possible. Discover what it takes to preserve North Dakota’s natural and cultural history. We encourage dialogue, questions, and comments!

Where Did You Find That?: The Importance of Archaeological Context

“Where did you find it?” This is, without question, the first thing you will hear any of our archaeologists ask when someone shows us an artifact. We are kind of obsessed with the “where” questions – where did you find it? Where did it come from? Where in the excavation unit was it found? What vertical level did it come from? Where was it in relation to (fill in the blank)? Where in the world did I put my trowel? (You wouldn’t believe how often I’ve asked the last one.) The “where” – technically known as provenience or context – is crucial to the artifact’s ability to tell a story. If you are a regular reader, then you already know that the object itself can provide some information about the human past. But if we don’t know its context, then it is pretty limited in terms of scientific value.

Field catalog

A field catalog for artifacts recovered during the 1951 excavation of Like-A-Fishhook Village in 1951 (AHP Archaeology files). Because we know which houses were occupied by Mandan and/or Hidatsa and which houses were occupied by Arikara families, knowing from which houses these objects originated is very important (House 4 was located in the Mandan-Hidatsa section of the village).

Imagine a projectile point that someone found in North Dakota. Perhaps they have mounted it in a frame in their home. From its shape and the technological style, I may be able to tell you that it is from the Archaic period. But that is about it. If it is an Oxbow point (for example), then it merely provides evidence that Oxbow technology is represented in North Dakota. It might be aesthetically beautiful, even ideal for exhibit. But it cannot tell us any more about human behavior and innovation in the past, which is actually what archaeologists are all trying to understand. Because at the end of the day, archaeologists are interested in understanding people, not things.

Now let’s imagine that the same point was scientifically excavated. We know from the additional excavation units around it that the point was found at a large camp site in Bismarck. Its vertical location (where it falls in soil stratigraphy) may tell us how old it is, or where it falls in time relative to other artifacts at the site. The artifacts found around it may help us understand what was going on in that spot. For example, if it was found in a pile of animal bone and cutting tools, we could infer that someone was likely butchering animals for food. If it was found in a pile of stone chipping debris and next to an antler pressure flaker, a different story emerges – perhaps this was a lithic workshop where stone tools were being manufactured. If a piece of charcoal found in its vicinity can be dated, then we can come up with a more exact age for the artifact. All of this information is documented during an excavation through extensive note-taking, sketching, photography, and mapping. And those records eventually make their way to the North Dakota Heritage Center & State Museum.

Field catalog cover

A field catalog from the excavation of the Flaming Arrow Village site (32ML4) in the early 1980s.

Field catalog entry

Entry made by crew member on July 20, 1971, while excavating the Hidatsa village of Amahami in Stanton, ND.

When I tell people that I am an archaeology collections manager, they typically assume that I only take care of artifacts. They are often surprised to learn that a huge and incredibly important part of doing archaeology includes creating, archiving, and referencing these paper records and photos. This also surprises archaeology students, who find themselves spending an inordinate amount of time sweating over notebooks or trying to draw wall profiles while wrestling graph paper in gusty winds during field school. This is actually a big responsibility from a preservation standpoint-- once the excavation is over, these paper records will comprise the most complete existing record of the site (or that portion of the site). In fact, when any archaeology contractor or state or federal agency submits collections for long-term curation, we require all the paperwork associated with their recovery from the field to be included.

General level/feature level excavation form

Plan map to go with general level/feature level excavation form

A general level/feature level excavation form, which is filled out for every excavated level (this one was filled out for the level that was at a depth of 95-110 cm). The associated sketch is the plan map drawn to illustrate what the bottom of this particular level looks like. It documents important observations like soil color and texture, artifact content and density, etc. This feature form is from an excavation at Double Ditch Indian Village Historic Site (32BL8), Feature 709, Ditch 4.

We curate these in acid-free, archival folders and boxes and index them now so they are easier for scholars to query when researching our collections. I have never had a researcher request access to collections without also requesting access to the associated paperwork. When we do not have the paperwork providing context for a given collection, the researcher often has to exclude those objects from his/her study. That should give you a sense of their importance!

Detail of House 3 entrance, firescreen (?) and primary fireplace

Cross-section of F28, House 3, firescreen (?) trench.

Photos of features in House 3 at Huff Village (32MO11), 1960.

So the next time you visit our State Museum or state historical site interpretive centers, remember that behind every artifact we are able to say anything about, there is likely a box of associated notes and photos that helped us tell that story.

Archaeology is Elemental: Geochemical Source Analysis of Obsidian Artifacts from North Dakota

Lithics, or stone tools and flaking debris, are among the most common artifacts found at archaeological sites in North Dakota. They can convey information to archaeologists about the people who made these objects, and they can also tell a much larger story of landscape use and cultural interaction. The rocks people eventually knapped into tools had to first be collected—sometimes this was done directly by the knappers themselves, and sometimes stone was acquired through trade with other groups of people. Lithic materials from North Dakota sites come from a vast area that includes the Northern Plains, Upper Great Lakes, and Rocky Mountains. Obsidian artifacts are occasionally found in North Dakota, but there are no obsidian sources within the state. Obsidian was prized by knappers for its properties. It is a high-quality, reliable stone with hardly any flaws, and it produces very sharp edges. It may have also been favored for its aesthetic value.

Map of regional lithic raw material sources

Regional lithic raw material sources. (State Historical Society of North Dakota)

Obsidian forms during volcanic eruptions when lava flows supercool upon contact with air or water, creating volcanic glass. Each volcanic flow has a distinct geologic and chemical signature, and the chemical composition of the obsidian formed from these flows is uniform throughout the source. Obsidian is composed mainly of silica (which gives it its glass-like appearance), but also contains trace elements such as zirconium, niobium, iron, and manganese. The ratios of these trace elements differ between obsidian sources, distinguishing them from each other on an elemental scale. Archaeologists specializing in geochemical techniques use instruments to analyze geological samples and determine a trace element profile for that source. Think of a trace element profile as a kind of fingerprint—although obsidian sources may be similar, no two are exactly alike. Once a geochemist has a fingerprint of the geologic source, it can be compared with artifacts made from obsidian. One of the most common instruments used to assess trace element composition is an energy dispersive x-ray fluorescence spectrometer (EDXRF). This analysis is non-destructive, which makes it especially useful for testing museum specimens.

Obsidian artifacts

Obsidian artifacts sent for sourcing (left to right: projectile point from Beadmaker; biface from Huff; biface from Shermer). (State Historical Society of North Dakota)

Previous research has shown that North Dakota knappers used obsidian from three main sources in the Yellowstone region: Obsidian Cliff (Wyoming), Bear Gulch (Idaho), and Malad (Idaho)1. This earlier study did not include artifacts from Mandan villages, and we were curious about trade patterns at these sites. The Mandans were key players in an expansive Northern Plains trade network during the Plains Village period, and certain villages may have controlled access to obsidian materials. Obsidian tools and flakes were selected from six Mandan villages and one Mandan campsite that date between AD 1300 and AD 1750. These 76 samples were analyzed by Richard Hughes, Ph.D., at the Geochemical Research Laboratory in Portola Valley, California.

Wyoming obsidian sources

Wyoming obsidian sources (courtesy Northwest Research Obsidian Studies Laboratory, www.obsidianlab.com)

Idaho obsidian sources

Idaho obsidian sources (courtesy Northwest Research Obsidian Studies Laboratory, www.obsidianlab.com)

Using EDXRF, Dr. Hughes concluded the obsidian artifacts from the Mandan sites came from the Obsidian Cliff and Bear Gulch sources. No artifacts were sourced to Malad. All sites but one had a combination of Obsidian Cliff and Bear Gulch artifacts, although in differing frequencies. The outlier was Huff, but only one artifact was submitted, and this was sourced to Obsidian Cliff.

What does this mean for patterns of exchange in the Mandan world? While this is a pilot study—that is, the first step of a larger project—we can hypothesize that use of Obsidian Cliff versus Bear Gulch materials at Mandan sites was not controlled by certain Mandan villages. Instead, obsidian imports into this region of North Dakota were more likely driven by the hunter-gatherers that controlled access to obsidian outcrops in the Yellowstone area. An expanded sample of Mandan obsidian artifacts will help refine our understanding of regional trade networks.

1 Baugh, Timothy G. and Fred W. Nelson (1988) Archaeological Obsidian Recovered from Selected North Dakota Sites and Its Relationship to Changing Exchange Systems in the Plains. Journal of the North Dakota Archaeological Association 3:74-94.