Excavations in Trench 39 South on Mound AB in 1996 revealed an extensive deposit of the Kot Diji phase occupation dating to between 2800 and 2600 BC. A geometric button seal (38) was found in the upper part of this rectangular Trench 39 South. White tags mark major features, such as hearths and floor levels. Above the highest white tag is a thick mud brick wall built during the later Harappa Phase that protected these important deposits from erosion.