A number of small sculptural elements, arranged in an apparently illogical manner, are dotted around the extensive, compact marble surface of the Camposanto, which forms the northern boundary of the Piazza. They are in the form of little faces or anthropomorphic renderings that tell us a great deal about the construction phases of the building, for they indicate the presence of craftsmen on the building site, each of whom is identified by one of these figures. This is one of the little faces carved in relief on a dressed stone during the first half of the thirteenth century, thus breaking up the smooth white surface of the wall.