The murder weapon: Two-foot, 82lb rock used to smash South African student to death as she was held down after being kidnapped and gang-raped is shown to court Rock used to bludgeon Hannah Cornelius to death produced in court The two-foot 82lb rock used to smashed student's skull after being gang-raped Experts say gifted student died instantly during the Stellenbosch attack Public gallery in court room gasped at size of alleged weapon shown to the judge Vernon Witbooi, 33, Geraldo Parsons, 27, Nashville Julius, 29, and Eben Van Nieberk, 28, stand accused at the Western High Court in Cape Town...