Fort McCoy ArtiFACT: Hammerstones

Courtesy Photo | Examples of hammerstones found on archaeological digs at Fort McCoy, Wis., are shown June 25, 2024. A hammerstone is used to apply direct percussion to a stone which might become a tool. The process is very much like using a hammer to drive nails — it requires force and precision. (Photo by the Fort McCoy Archaeological Team)  

FORT MCCOY, WISCONSIN, UNITED STATES

06.25.2024

Courtesy Story

Fort McCoy Public Affairs Office           

Archaeologists working at Fort McCoy have identified and investigated hundreds of archaeological sites and found hundreds of thousands of artifacts. The most common artifacts at Fort McCoy are small, chipped pieces of stone which archaeologists refer to as debitage.

Creating stone tools such as spear points, arrowheads, and knives is a reduction process which involves taking a certain type of stone and breaking pieces off to shape it into the desired final product. To begin this process of shaping a stone into a tool requires an object which has been in our toolkit for as long as we have been using tools — the hammerstone.

A hammerstone is used to apply direct percussion to a stone which might become a tool. The process is very much like using a hammer to drive nails — it requires force and precision.

To remove bits of stone to shape a tool, the stone must be hit in a certain spot with a certain amount of power. If you don’t hit a nail on the head, the nail is likely to bend. If you hit a stone with a hammerstone the wrong way, you may not be able to remove the pieces you want, or the stone might break and become unusable. Worse still, the force might rebound back and break your hammerstone.

River-worn pebbles and cobbles, especially volcanic rocks like basalt or quartzites, make good hammerstones because they are durable. Unfortunately, even the most durable hammerstone will eventually break.

Using the same facet of a hammerstone repeatedly creates pits and dimples on its surface (numbers 1 and 2 in the related photo point to this effect on the complete hammerstones), and those stresses affect the internal integrity of the hammerstone as well. This is helpful to archaeologists, in that this evidence of battering is necessary to identify a rock as a hammerstone.

The photo which accompanies this article shows two complete hammerstones (A) and three hammerstone fragments (B), and these five artifacts represent approximately 17 percent of all the hammerstone artifacts which can be found in the Fort McCoy collection held at the Mississippi Valley Archaeology Center at the University of Wisconsin-La Crosse.

The 30 hammerstones or hammerstone fragments seems like a small number when compared to the nearly 35,000 chipped stone waste flakes in that collection. Of course, a single hammerstone could be used to help shape dozens of stone tools before it breaks and would most likely be carried away by the toolmaker after finishing shaping a tool.

Furthermore, a second look at the five hammerstones and hammerstone fragments can help illustrate why the hammerstone class of artifacts might seem underrepresented in the archaeological record of Fort McCoy.

The artifacts in the picture look like normal, average rocks and broken pieces of rocks. This is why being able to record where artifacts were found and especially what was found next to them or in the same vicinity is so important to archaeological research. The hammerstones and hammerstone fragments shown in the picture were found in archaeological excavation units which also produced hundreds of chipped stone waste flakes along with stone tools and stone tool fragments.

As a stone tool gets farther along in the shaping process and is closer to being finished, direct percussion with a hammerstone becomes ineffective. The maker will need to use softer percussion tools like bone or antler or even copper or use indirect percussion to focus the force in a very precise way in the same way carpenters and construction workers will use a nailset or nail punch to sink a nail or pin below the surface of a piece of wood.

Unfortunately, most of the items which would have been used for soft-hammer percussion or indirect percussion do not survive being buried for hundreds or thousands of years and are therefore even less represented in the Fort McCoy archaeological record than hammerstones.

All archaeological work conducted at Fort McCoy was sponsored by the Directorate of Public Works Environmental Division Natural Resources Branch.

Visitors and employees are reminded they should not collect artifacts on Fort McCoy or other government lands and leave the digging to the professionals.

Any individual who excavates, removes, damages, or otherwise alters or defaces any post-contact or pre-contact site, artifact, or object of antiquity on Fort McCoy is in violation of federal law.

The discovery of any archaeological artifact should be reported to the Directorate of Public Works Environmental Division Natural Resources Branch.

(Article prepared by the Fort McCoy Archaeology Team that includes the Colorado State University’s Center for Environmental Management of Military Lands and the Fort McCoy Directorate of Public Works Environmental Division Natural Resources Branch.)

• Date Taken: 06.25.2024
• Date Posted: 06.25.2024 16:23
• Story ID: 474827
• Location: FORT MCCOY, WISCONSIN, US