An Artifact's Journey from Start to Finish

Have you ever wondered what happens to an artifact after it is dug up? 

Well, several things happen along the way. Let's start in the field. First, the artifact could be removed during excavation and added to an artifact bag or it could be found in the wet screen where it gets left to dry, and then later placed in an artifact bag. You may now be wondering, "Why do archaeologists use artifact bags and how can they tell each bag apart?" Each bag must have its own tag, or label, and each tag has detailed information about where the artifact was found. For example, every excavation unit (hole in the ground at a site) has its own coordinate location based on the site datum (or zero marker) at the site. This is important because it can tell us and future researchers where the excavation units were placed and where an artifact came from on the site. This past year, my unit was N3 W8, meaning that the 1 by 2 m hole was located North 3 meters from the site datum point and 8 meters West. This is not enough information though; we need more!

The site comprises several different soil “layers” (dirt). The first layer that we dig through at Fort St. Joseph is the alluvium which is dirt that was brought in and left by the St. Joseph river. This layer varies in depth at the site and is much deeper near the edge of the water. The next layer, the plow zone, lies just under the deposits left by the river and corresponds to the time when the area was farmed. We find many artifacts in this soil layer. However, they are often disturbed from their original resting place because when the plow came through the area, it churned up the dirt, disturbing the artifacts. The final layer at Fort St. Joseph is referred to as the occupation zone. It is just like it sounds; this is the layer where we find signs of undisturbed habitation. These soil zones are further divided into 5-cm arbitrary layers. By measuring from a fixed point at each excavation unit, the unit's datum, we are able to determine the depth of every layer we remove from the site. This information is then added to the tag for each artifact bag. So now we know what unit the artifact came from, what soil layer, and the the layer's depth. We can essentially record the artifacts 3D location at Fort St. Joseph.

Once we take the artifacts to the lab, we must first clean the artifacts. This is where the tags come in handy. Each bag is taken separately, and the contents are washed with water or dry brushed depending on the material. For example, metal or highly fragile artifacts are dry brushed, and objects like bone or seed beads can be washed gently in water. Once the artifacts are washed, they are placed together with the tag on a drying rack. After the artifacts dry, they are then sorted by types or like items. All necessary information is taken from the field bag tag during the sorting process, and a copy of this information is placed on a new tag which we then place in a small bag with each artifact type. Sometimes, we find that things we thought of as artifacts were just the dreaded mudstone. Other times, an artifact, like an iron nail, can be covered in excess rust/dirt. If that happens, we may take a dental pick and scrape off some of the excess. In this image, I am cleaning an iron knife blade fragment. It is vital that metal artifacts like this do not come in contact with water. We want to save the artifact's integrity, so we also add a silica packet to the bag. 

After we discovered, cleaned, and sorted the artifacts, we then have to inventory them. Erika maintains a database containing the artifacts discovered over the past 25 years so we work with her closely in this step. It is also during this stage that we double-check all our information on the tags. We must maintain our record keeping throughout the process so that no artifacts can be lost or mislabeled. From start to finish, the critical information follows the artifact. This entire process allows us to collect data that can be used in research like the projects that we have been recently sharing on our blogs. 

John