Wear of stone used to manufacture axes in the Neolithic settlement at Makriyalos in Northern Greece

Archaeologists have excavated examples of worked stone tools of several different types of serpentinite at the Neolithic settlement at Makriyalos in Northern Greece including a pistachio green serpentinite and a dark black/green serpentinite. The ancient stone tools had clearly been both cut and polished, but it was not evident, however, how they had been worked or what materials had been used for the tasks.The aim of this work was to investigate methods by which the sawing and polishing could have been accomplished. Accordingly, two modern samples of the relevant stone were collected from the environs of the archaeological site, on which both strength and porosity tests were carried out. These indicated that the black serpentinite was stronger and less porous than the pistachio serpentinite.Pin-on-disc wear tests were then carried out using both quartz and sandstone as the pin material. Loads and sliding speeds representative of those that could be applied by a human were used. Tests were run in wet and dry conditions. The results indicated that under certain combinations of materials and test conditions both sawing and polishing could be achieved. Adding water weakened the pistachio green serpentinite so wear was higher, whereas with the harder, less porous black/green serpentinite wear was lower with water. The sandstone wore down quickly in all cases, but was still able to wear the serpentinite enough to allow sawing to take place.The results have helped archaeologists to understand what may have happened with their excavated samples, although more tests with different materials are required, for example rubbing serpentinite against serpentinite.