Summary of Obsidian Sourcing
Why study obsidian? | Location | What does it tell us?

Why study obsidian artifacts?

    One of the broader goals of our collaborative project is to understand ancient social relations within and between communities. There are several ways to do this. Tracing similarities in language is one way to show connections among people. Likewise, similarities in “material culture” (projectile points, baskets, house styles) is another way. Another way is to track down the origin of the foods and materials we recover in archaeological sites.


    Assorted obsidian artifacts from Grief Point site

    Determining the origin (also called the source) of obsidian artifacts (Figure x – photo of obsidian). is a valuable tool for tracking ancient social relations. This is because each time a volcano erupts, the magma is composed of a distinct combination of minerals. Once we know the distinct combination of each eruption and each volcano, it is possible to compare the make up of the artifacts we find archaeologically to this information. There is now a data base that includes all the obsidian sources in Oregon, Washington, and British Columbia. These data allow us to “source” most obsidian artifacts recovered from BC archaeological sites. It is important to note that this comparison only tell us the source of the raw material used to make the artifact, it does not tell us where the artifact itself was made.

    There are several reasons why obsidian is a good material for tracking social relations. First, it is a highly valued raw material for artifacts. Ancient stone tool makers sought materials that were fine grained and would fracture the way they expected it to when they were forming the rock into a usable tool. In addition, the fine crystalline structure of obsidian was valued not only because it behaved in predictable ways when manufacturing tools, but also because the glassy material produced a fine, razor sharp edge. But, when ultimately makes obsidian so well suited for tracking social relations is that this highly valuable tool was in short supply in most parts of British Columbia. Thus, in order to get this raw material, people would have either 1. lived close to the source, or 2. had social (kin?) or economic relations with the people who did live close to the source.

Why study obsidian? | Location | What does it tell us?
 ©2012 SFU Archaeology &
Tla'amin First Nation