Features of a Flake

Back in 2015 I was dropped off by a helicopter in the middle of a large muskeg to assess a cutblock for Alberta-Pacific Forest Industries. After trudging my way through the swamp to the cutblock, I found a very prominent but small hill. I put my shovel in the ground and I found one large, beautiful flake. I tested out the rest of the landform but found nothing else. I flagged the site for avoidance by harvesters and made my way back through the muskeg to be picked up by the helicopter.

When I got there I told the pilot that I found a site. He responded “Really? This is the middle of nowhere. Why would anyone be out here?” To which I replied, “People were everywhere, man.” The pilot was skeptical and asked to see what I found. He said, “That’s just a rock that was broken by your shovel.” I responded by saying, “I can give you eight reasons why this is a legitimate artifact…”

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The above artifact is the “textbook flake” that I found that day. It has all the features that we typically look for in determining if it is natural or a rock that was broken by a human in the past. These features are:

1. Bulb of percussion: A bulb that forms directly below where the hammerstone struck the core. This is what causes the flake to be popped from the core. If a rock is broken by heating or freeze-thaw this bulb will not be present.

2. Platform: The flat area where the flintknapper would strike the core to pop the flake off. These areas are sometimes prepped to be struck by rubbing the hammerstone on the edge to strengthen the edge and remove any micro-fractures that may cause the rock to break in an unintended way.

3. Percussion waves: Caused by the force travelling through the flake.

4. Eraillure Scar: Small flake scar on the ventral surface of the flake which is the result of the rebounding force from the percussive force.

5. Termination: This flake has a feather termination. This is a perfect detachment of a flake from a core. Desirable because the end of the flake is sharp without need to resharpen or retouch. This means that the flake is a ready tool that can be used to cut or scrape. Other types of terminations include: hinge, step, and overshot terminations. These are usually an error by the knapper or flaws in the core.

6. Flake Scars: Areas on the dorsal surface of the flake where flakes were knocked off during earlier stages of tool making process. The coincidence of these being present on a naturally broken rock are impossible.

7. Material: The material of this flake is a fine grained chert. This is not a rock that would naturally be found in this immediate area. There were also no other rocks present in the shovel test or any of the other shovel tests that were dug that day.

8. Context: Sometimes when rocks are crushed by heavy equipment they can break in a similar fashion but this was found pre-disturbance. Additionally, the force from me putting my shovel into the ground could never possibly break a rock in this fashion. I am not that strong.

It is not often that we have all of these flake features present. Sometimes if a flake is broken we might not be able to see the bulb and platform or the termination. We usually try to find at least two of these features to call something an artifact. To convince a non-archaeologist a flake is genuine you might need all these features present. I feel like I convinced the pilot that this was a real artifact but I think he only responded by saying “interesting.”

 

We Know How Old Stone Points Are, Right?

Back in September of 2017, I found what would probably be one of the coolest artifacts that I will ever find in my field survey career. My coworker Vince and I got up one fateful morning and set out on our four hour quad ride into one of the most beautiful areas in Northern Alberta: the Swan Hills. I have been working in the Swan Hills area for a few years now and every time I come back, I am always amazed by the broad vistas and pristine valleys that cut through this segment of the Alberta Foothills.

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On the trail near Goose Tower, Swan Hills, AB.

We were checking out a cutblock on the edge of a broad muskeg flat with a small stream. It was pretty swampy on the way in, but once we got closer to the stream, the land rose up into a nice, narrow little ridge that gave a good view over the stream. After walking around for a bit, Vince and I settled on a place to start digging. Normally, it takes a bit of time going through the screen before you can find the small stone flakes that we typically find. This time, I only had to flip over the root mat to see the top half of a stone blade stuck in the rootlets. A few seconds later, I pulled out the base of the same blade from the loose sediment, revealing a complete spear point buried only a few centimeters below the surface.

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The point seconds after I pulled it from the ground.

You can only imagine my excitement once I pulled this beautiful specimen out of the ground (I think I was making noises akin to Homer Simpson drooling over a doughnut). It is hard enough to find artifacts in the Boreal Forest, let alone to find a tool! My first thought as soon as I pulled it out was that I had found an Alberta Point. This is a type of projectile point that dates to around 9500 and 8000 years ago and is part of what is known as the Cody Complex. Alberta Points commonly have square stems that would have been hafted into a spear shaft, along with broad distinct shoulders and wider tapered blades. It seemed to be a good fit for the style of the point that I had found so I put Alberta Point in my notes and went about my day.

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The two pieces fit perfectly together, but it’s a bit awkward holding it like this!

Back at the lab, I started flipping through my reference books. I began to realize that what I had found didn’t really fit with what we know about Alberta Points. The shoulders weren’t as square as other Alberta Points and the blade was a little too broad and less lance-like. I also noticed that the shape of the point closely resemble ones found at Hell Gap sites, dating to between 10,000 and 9,000 years ago (before the Alberta points and the Cody Complex). During this period, we see that First Nations ancestors were making similar large spear heads, but with a broader blade and slight, indistinct shoulders. So the spearhead that I found could also belong to this time period. However, the story doesn’t end there. To complicate matters more, there are also similar kinds of projectile points being made around Lake Athabasca in the northeast corner of the province. During the Early Taltheilei Phase (2600 to 1800 years ago), the caribou hunting people living on the shores of Lake Athabasca were making similar looking large spear and atlatl dart points. The point I found could fit into any one of these three possibilities.

So what kind of projectile point had I found? If we can identify the style, we can make inferences on the age and archaeological culture that was present at the site. Being able to place an age on a site is often difficult to do for Alberta sites, especially sites in the Boreal Forest. The lack of organic preservation at many sites means that radiocarbon dating is often not possible. Also, most archaeological sites in northern Alberta have very little stratigraphy, meaning that you will find 13,000 years of history in about 20 cm of soil. Even this artifact, which may be anywhere from over 10,000 to 2000 years old, was found only 5 cm below the surface. So if I were to determine how old this site was, I would need to be able to positively identify the type of projectile point that I had found. So what did I find? How was it made? Where did it come from? The answers to these questions can tell us about the people who made the artifact.

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Both sides of the spear point.

First off, the material. The point is made of fine-grained quartzite, a lithic raw material that was frequently used in Alberta all throughout history. There are a lot of advantages to working with quartzite. As a material it is very strong and durable, which means that the edge of the blade will hold longer than other materials like obsidian. This also means that it is extremely difficult to work with. When we try our hand at flintknapping today, we often start with obsidian, chert, or flint because these materials will fracture more easily and predictably than others. Pick up a raw quartzite cobble, and you’ll find that you be bruised from trying to crack it open.

Quartzite is also very common. Almost every stream, creek, and river valley is filled with a variety of quartzite cobbles. You don’t need to import it thousands of kilometers, unlike Knife River Flint or obsidian. Not all quartzite is the same quality, but there are well documented sources of high quality quartzite and sandstone throughout the province, like the top of the Grizzly Ridge by Swan Hills or in the Oil Sands around Fort McMurray.

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Corey standing on a stream bed full of quartzite cobbles.

In fact, this point is made from a type of quartzite that is commonly known as ‘Salt-and-Pepper’ because of the small black specks in the largely white stone. This material has been found all over Northern Alberta, but it is most commonly reported around Fort McMurray. While no source has been officially documented, archaeologists who work in the Oil Sands region often report seeing raw cobbles and boulders of ‘Salt-and-Pepper’ quartzite in the creeks flowing into the Athabasca River. It is very likely then that this point was made from a cobble that came from the Fort McMurray region. Whether the person who made the point carried from Northeastern Alberta or if it made its way by trade, we don’t know. However, it does show us the vast ancient networks that connected the First Nations across Alberta.

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Possible pathway for Salt and Pepper quartzite from Fort McMurray.

So we know where the raw material for the point came from, what about how it was made? What can the shape and design tell us about the people who made it? One way to study this is to look at the flake scars, the ridges and concavities left when pieces of quartzite were struck from the point. Most of the time with finished projectile point, or those that have reached the end of their life as a usable tool, we will see that the edges will be very uniform and straight, with small flake scars along the blade where the tool was resharpened. However, this artifact is very rough, the edges are irregular and chipped and the blade has large long flake scars covering the surface. Based on these traits, it appears that this point was unfinished, and looking at where the break is, it was likely broken when they were trying to make the blade thinner. This point is what would be called a ‘Preform’, a roughly worked projectile point that has not been attached to a haft yet. Preforms can take a variety of shapes and forms, but they often resemble the final point style.

So now that we understand that we are looking at an unfinished point, it better explains why the shape of the artifact does not perfectly match other Alberta points. However, that doesn’t help us to determine if it is an Alberta, Hell Gap, or Taltheilei projectile point. The implications of assigning the point one of these time periods is significant, because it would move the occupation of the site from a period where Giant Bison and Ice Age mammals roamed Alberta during the Hell Gap Phase, to an environment more similar to what we see today during the Taltheilei Phase. Personally, I think that the point from GfQa-5 is more similar to projectile points and preforms that have been dated to the Hell Gap period. The shape of the shoulders, base, and the blade all seem to better match the style of these points than Alberta Points, and the points found at Taltheilei sites tend to be smaller and narrower. A cache of similar looking spear points were found near Eaglesham in northwestern Alberta, and the archaeologists who studied these points concluded that they were likely unfinished Hell Gap points. It seems likely then that the spear point I found would fall into this time period. However, this is still based on very general characteristics, and it could still easily fit within all three of these categories. Until we have more information, and we excavate more archaeological sites, we are often left with our best guess.

Peace River Chert Biface

In the summer of 2016, this tool was identified while inspecting the exposures along an in-block road for Boucher Bros Lumber. It is likely the bottom portion of a biface that broke during manufacture or use. It is made from Peace River Chert, a material common to the Peace River region.

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Blasting Powder Cans

Here is an example of a unique artifact type – it is a large metal can that once contained blasting powder. We often find these cans associated with the old historic railways found throughout the province. This particular can has an inscription on the base which helps us to identify the contents of the can. In this case it also has the name of the producer. This information can help us to narrow down the age of the can.

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This is a rubbing from the base of the can, it sure makes it easy to identify what the can once held.

Asymmetrical Knife

This week we feature a picture of an asymmetrical knife found north of Lac La Biche at a site called Buffalo Beach. The knife has one rounded retouched cutting edge and the other edge is straight. The notched knob at the bottom of the artifact is where the knife would have been attached to a handle. The handle was likely made from an organic material that does not preserve as well as stone (for example bone, antler, wood, etc.). The style of this knife does not match any previously recorded artifacts found in Alberta.

End Scraper

This week we feature a stone tool found upstream on Fall Creek, about 55 km west of the community of Caroline, AB. We were undertaking an assessment for Sundre Forest Products and testing a flat area overlooking the creek (shown below) when Ryan found the end scraper shown above.

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A “scraper” is a type of tool that is usually unifacial, meaning the stone was worked on one of its sides (or faces) only. Compare the two sides shown in the image above and you’ll see the one shown on the left is much smoother, except for a small piece that may have been broken off when digging the shovel test. The face of the scraper that is worked typically has pieces chipped off on the side or end in order to make a thick and strong edge. This is the scraping edge that could be used to prepare hides.

Unifacial working and a thick edge are the two main criteria used when identifying an artifact as a scraper, so as you can imagine there are a lot of different styles of scrapers found at archaeological sites. Just take a look at the beautiful example Reid describes in this blog post.

Regardless of what style of scraper you’ve found, a close look at the edge of these artifacts can reveal some “use wear,” when the edges become chipped, polished or worn down through the process of scraping hides, bone, wood or other softer materials. As a result of this wear, scrapers would occasionally need to be resharpened and the tools would become smaller and smaller through the resharpening process. It’s possible this scraper was considered too small to be of any more use and so was thrown away only to be found by us, perhaps thousands of years later.