A paleolithic petrified human skull dating from the Pleistocene period was found in a concrete geological bed in a cave by the sea in Apidema, Mesa Mani, Greece. The cleaning of the skull in the laboratories of the National Archaeological Museum, Athens, proved that the skull belongs to an ancestor of modern man and is an important discovery for paleoanthropology in Greece. The cleaning of the skull was performed with such tools as dental grinding wheels and the <i>S.S.White</i> air abrasive unit.