A perfect unicorn seal found in Trench 49E, Harappa. The craftsmanship and balance of the three fish signs, the arrow and two strokes with the so-called unicorn's head and sacred relic is remarkable. Excavations in 1997 at the southeast corner of the Mound F "granary" area were undertaken to recover a full sequence of pottery, architectural features, and inscribed objects. Here workers have found a seal near the base of the excavations in Trench 41NE that dates only somewhat later than the original "granary" structure. This seal dates to approximately 2200 BCE, at the transition between Harappa Periods 3B and 3C. The precise function of the twelve units of halls that make up this complex is still not confirmed, but excavations between 1997 and 1999 revealed that there is no evidence to suggest they were used for storing grain or other consumable commodities. There are three major building phases of this complex and the currently visible structures date from the middle phase, around 2200-2000 BCE.