Mechanical damage of a crystalline rock having experienced ultra high deviatoric stress up to 1.7 GPa

► A gabbro specimen has been severely damaged by a high deviatoric state of stress. ► A test on damaged specimen shows a substantial decrease of uniaxial compressive strength. ► Elastic wave velocity measurements show a drop in Young's modulus. ► Thin section highlighted the damage due to intra-crystalline micro-cracks mostly in plagioclase.