The Start of AiA at SERC

We started our excavation by walking around the remaining foundation of a building and looking at what makes this a site. So, we were looking for anything that demonstrated human activity, like broken glass, nails, ceramics, bricks, altered landscape; we even looked at how the trees in the area were arranged differently too!

This piece of Aqua Glass was found in one of our STPs.

This piece of Aqua Glass was found in one of our STPs. Source: Joe Harden

Then came the fun part! We started digging; we dug Shovel Test Pits (STPs). These are one-foot by one-foot holes that help us create a range of human activity; they give us information about how far away from the building humans were and what they may have been doing, and if an STP comes back empty it still gives us a lot of information, meaning that human activity didn’t extend that far away from the building and it gives helpful information on the stratigraphy or layers of the soil. All of the STPs are carefully measured from a fixed point, called a site datum, on the site that will not move. So we chose one of the brick piers and took a compass and labeled it as 1000N and 1000E and every STP from there was measured in increments of 25 feet in any of the cardinal directions, for example, if the STP was 25 feet south of our point and 25 feet west, the STP would measure at 975N and 975E because calculations are always made in regards to north and east. A brick pier is used as a building foundation. They are used for wooden houses to raise the floor of the house off the ground so that the wood doesn’t sit on wet ground and rot. We’ve all seen a brick pier before, now we know what it’s called! The bricks are stacked and mortared together in each corner and usually one on each side of the building as well.

Milk Glass

Milk Glass found in an STP. Source: Joe Harden

In our STPs we found many different indicators of human activity: different types of glass, different types of ceramics (plates, bowls, etc.), nails, charred wood, oyster shells, even a vinyl record! Glass and ceramics differ by color and texture due to the different time periods, styles, uses, and technologies available to produce them. We found ironstone, a ceramic that is white but will have a rust color in the creases; pearlware, a ceramic that will have a bluish tint; creamware, a ceramic that is off-white and usually has yellow or green in the creases; among many others. In regards to glass, we’ve found pieces of milk glass, glass that is white through and through; manganese glass, glass that appears clear but actually has a slightly purple tint due to the chemical (manganese) used to produce it; aqua glass, glass with a noticeable light blue tint from the iron impurities in the sand used to produce it; and many more. I could list them all but this would go on for ages. A link to different types and descriptions can be found here.

Manganese Glass

Manganese Glass found in an STP. Source: Joe Harden



Shark’s Tooth found in an STP. Source: Trish Markert

Also in our STPs we’ve found this layer of sand, and as we started moving down the hill this layer of sand was found closer and closer to the surface. And then a team member found a shark’s tooth! We originally had a hypothesis that where we were digging used to be some type of water system, but the discovery of the tooth made us more sure! So this site may have been a Tidal River of the Chesapeake Bay at some point in the past!


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