Generally,  you can''t differenciate many types of rock using mechanical test becaurse its material sometimes have similars properties

Hi,

Ideally, these two moduli determined by means of the two mentioned testing configurations should be the same or there might be minor differences. However, due to the geological nature of different types of rock resulted from their formation and source, there might be a faulty joints located at different directions. These joints make the deformability in one testing direction different from the other. Therefore, a considerable difference in the moduli values might exist. From my experience, another source of variability might occurs due to the different instrumentation setup. The latter needs to be managed in an appropriate manner. Kind Regards,

Thank you for your help