The Equotip (Proceq) Hardness Tester (EHT) (or durometer) is a portable device consisting of a piston ending in a 3 mm diameter cylinder that impact against the surface of the material to be tested. In this sense, the Equotip Hardness Tester operates on the same principles as the Schmidt hammer (SH), which has already been used in several archaeological studies, including the mechanical characterization of lithic raw materials. By using the Equotip Hardness Tester, this study objectively assess and quantifies the possible effects of these specific features of lithic raw material on mechanical forces similar to those acting during knapping. The dispersion and variability of the hardness values detected by this device might be used for assessing and quantifying, in a relatively objective way, the level of continuity, homogeneity and isotropy of lithic raw materials, and therefore be used for appraising the specific mechanical characteristics (such as elastic response and fracture toughness) that influence their knapping suitability.