The other significant find on Mallory's body was a severe, golf ball-sized puncture wound in his forehead, the likely cause of his death. The unusual puncture wound is consistent with one inflicted by an ice axe, leading some to conclude that, while Mallory was descending in a self-arrest "glissade", sliding down a slope while dragging his ice axe in the snow to control the speed of his descent, his ice axe may have struck a rock and bounced off, striking him fatally.