A clock-face medallion is a center medaillion that makes up a unique design only found in the village of Tafresh in Iran. Tafresh is a village East of the city of Hamadan. Rugs are woven using the, Hamadan Weave, which is a single-wefted structure. The medallion always has sixteen segments, not twelve. Other similar designs are used in Tafresh that don't use the clock-face medallion. See one on the next clip.
Note: This rug has great detail because of the fine weave which allows for a more curvilinear effect.