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.