Obsidian and Ancient Trade Relations

Obsidian (Volcanic Glass) and Ancient Trade Relations on Lasqueti


A while back I asked Lasquetians to share with me any ancient artifacts collected

from Lasqueti that were made of obsidian (volcanic glass). This is part of a larger study

on ancient trade relations that I am conducting on the Sunshine Coast. Four people

responded to my call. Two of the artifacts were probably not originally from Lasqueti

(i.e., they were collected on someone’s holiday in Mexico), but ended up in people’s

Lasqueti collection. The other two were in deed from Lasqueti archaeology sites. These

two, in combination with several artifacts from the Sunshine Coast, give us some insights

into ancient social relations within and between communities in this region.

Why study obsidian artifacts?

Archaeologists have two means for studying ancient social relations. The first is

by looking for similarities in the form of artifacts (projectile points, baskets, house

styles). This research is based on the assumption that shared styles indicate shared ideas

and thus communication. Another way to understand past social and economic relations

is to track down the origin of the raw materials used to make the artifacts recovered in

archaeological sites.

Obsidian, formed by the rapid cooling of volcanic magma, is ideally suited for

this second method. This is because the magma associated with each volcanic eruption is

composed of a distinct combination of minerals. Once "we" figure out 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 are several reasons why obsidian is a good material for tracking social

relations. First, it is a highly valued raw material for artifacts because of its fine

crystalline structure. It’s fine structure means both that it fractures predictably during

tool-making and it will produce a razor sharp edge. But, what ultimately makes obsidian

so well suited for tracking social relations is that this material is in short supply in most

parts of British Columbia. Thus, in order to get obsidian, 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.

Where do obsidian artifacts in the Sunshine Coast region come from?

Based on just 19 obsidian artifacts, we are beginning to get a picture of ancient

trade relations in this region in the last 2000 years or so. In general, obsidian in this

region comes from four sources. From north to south, these are 1. Kingcome Inlet in

central B.C, 2. Mt. Garibaldi in Squamish, 3. Whitewater Ridge, in central Oregon, and

4. Gregory Creek, just east of Whitewater Ridge, Oregon.

Both the Kingcome Inlet and Garibaldi obsidian are of only moderately good

quality. This is because they have some larger crystals in the rock that makes the

obsidian fracture less predictably during tool manufacture. Thus, all things being equal,

neither of these sources should have been preferred by ancient people. That is, unless

these sources were the only ones that were socially and/or economically available to

them. Today, the Kingcome source is well within the territory of Kwakwakwakw First

Nations, and Mt. Garibaldi is within Squamish First Nations territory.


What does all this tell us about social relations in the past?

In general, there are clear differences in the origin of the obsidian artifacts found

in this region. Obsidian from Lasqueti and sites south of Powell River on the Sunshine

Coast come from central Oregon and Mt. Garibaldi (Squamish). This suggests that the

people who lived on Lasqueti and nearby settlements were more closely affiliated with

folks further south than to the north. This pattern roughly fits with the social-linguistic

break between the Tla’amin and Sechelt First Nations today.

Moving northward, the pattern changes. At Powell River sites we have both

Garibaldi obsidian, but also the Kingcome Inlet source. Further north still, north of

Powell River and into Desolation Sound, there is a clear preference for Kingcome

obsidian. The relative abundance of Kingcome artifacts in the northern sites, and the mix

of Kingcome and Garibaldi sources in the Powell River sites, suggests that there is a shift

in trade (and kin?) connections somewhere around what is now Powell River. That is, it

seems that people living north of Powell River looked more northerly for their

social/economic relations, while the folks to the south of Powell River were more

connected to the people further south.

Of course, as we figure out the source of more obsidian artifacts found while

excavating, or in people’s personal artifact collections, we will be able to fine-tune our

story. In particular, I am curious how this pattern changes over time. For instance, at

about 2000 years ago, large villages are established on Lasqueti and elsewhere in this

region, which undoubtedly changed how people interacted. Then, about 1000 years ago,

we start to see "defensive sites" on Lasqueti and elsewhere in the region. As we well

know from modern times, conflict can result in dramatically altered trade relations and

the same was undoubtedly true in the past.

As always, please contact me if you have any questions/ideas/comments about Lasqueti’s

archaeological heritage. dlepofsk [at] sfu [dot] ca