All the axes are of Cretan materials. The majority, fifty-nine out of seventy-one, are of altered basic igneous rock consisting of various minerals, usually with much chlorite and serpentine. Group A is called serpentine as this mineral is predominant. In appearance the axes are blue/grey/black mottled, sometimes with brown mottling also. Group B is called greenstone since the minerals epidote and chlorite are present in large quantities and the specimens have a distinct greyish-green appearance. Group C is again altered basic rock, including chlorite and serpentine, though neither predominates.
There are a number of outcrops of chlorite and serpentine among the limestones of Crete, especially in the northern and southern foothills of the Mt. Ida massif.
Two axes appear to be of haematite, which occurs in Crete, two of limestone and one of schist. The materials of seven others are not certain, though several are probably of altered basic rock (see The Catalogue).
The materials agree with those of other stone axes from Crete, for serpentiniferous basic rock and greenstone examples have been picked up in various parts of the island. Greenstone and haematite were the predominant materials of the Late Neolithic axes from Magasá near Palaikastro.