Designated MAE 621. The Exterior surface is not consistent in coloring as it turns from brown to black as the neck/rim transition. The rim is highly eroded on the exterior side. The interior surface appears to be coated in some sort of soft and light corrosion over the light-colored slip. Hardness is in fact somewhere between 3 and 4. A soft and brown sherd, like a perfect cookie!
From Interior to Exterior