The 40 KG rock had been used to cover a borehole and was slammed down on Hannah Cornelius’s head twice as she was held down, a court was told.
The fatal blow was delivered after at least three men had taken turns to rape the gifted scholar.
Hannah, 21, would almost certainly have died instantly according to experts. However, to make sure, one of her killers also plunged a knife into her neck.
Vernon Witbooi, 33, Geraldo Parsons, 27, Nashville Julius, 29, and Eben Van Nieberk, 28, face charges including murder, kidnap, robbery and rape.
The chilling exhibit was lifted with a struggle onto a desk before the judge at the Western High Court in Cape Town, South Africa, by two strong security guards.
Members of the public gallery in Cape Town gasped when the rock allegedly used to kill Hannah Cornelius was produced to the judge in the court room.
The 21-year-old girl was raped and murdered in Stellenbosch, South Africa, after she and her male friend were carjacked by four men in May last year.
It was said that magistrate’s daughter Hannah and a friend Cheslin Marsh, 22, were kidnapped after she gave him a lift home in May last year at midnight.
She had parked her blue VW Golf â€“ a gift from her grandmother – outside his flat but as they parked a gang of four men attacked them opening both doors.
They put a screwdriver to her chest and put a knife to the back of fellow student Mr Marsh and threatened to kill him.
The court heard one of the gang shouted at him: ‘Sit still or she dies’.
Mr Marsh was robbed off cash and his phone and locked in the car boot and then the gang drove to a drug dealers home to buy drugs and smoked crystal meth.
Hannah was wedged between two of the four men in the back seat of the VW and the gang drove out of the upmarket wine producing town of Stellenbosch.
They pulled over and took Mr Marsh into the bushes and made him lay his head on a rock on the ground and then battered his skull with house bricks.
Ms Cornelius was dragged from her car and raped by at least three of the men, before they stabbed her in the neck and crushed her skull with a large rock.
Parson’s tattoo’s included crossed swords, a gun, a grotesque sketch of a naked headless female with legs spread open and shoulder stars showing his rank, the court heard.
The brutal assault only stopped when the gang were convinced that he was dead.
That afternoon Marsh recovered consciousness and staggered to a nearby home suffering severe head injuries and a broken arm to raise the alarm about Hannah.
Unknown to him her body had been found earlier several miles away dumped by the road and a huge police search was already underway for him and the gang.
She had been dragged into bushes at a vineyard and gang raped by at least three of the men in what was described in court as an ‘extremely painful’ ordeal.
Hannah suffered severe vaginal and cervical injuries in the prolonged attack.
When it was over it is alleged that the gang then found the large boulder covering a water borehole nearby and manhandled it across to where she was laying.
Heavy bruising on her arms show she had been held down and it is believed that probably several of the gang lifted the huge rock and dropped
Forensic pathologist Dr Deidre Abraham who carried out the autopsy on Hannah confirmed that her murderers dealt the fatal blows by dropping the rock twice.
She said: ‘The skull is made up of very strong bones indeed. It is not easy for a skull to break or crack unless a lot of power is used to actually break the skull.
‘The blunt force injuries to her head were very rapidly fatal’ she said.
Two workers Conrad Booysen and Flippie Matthee told the court they were repairing a borehole pump at Groenhoek Farm near Stellenbosch the day before.
After they removed the pump from the bottom of the well Mr Booysen said they placed the rock over the hole to stop people or animals falling in after dark.
Mr Booysen, 54, said the rock was so heavy it took the two of them to move it.
Three of the defendants, Witbooi, Julius and Van Nieberk admit that they were present but claimed they only robbed the pair and did not commit the rape or murder.
The court was shown yesterday photo’s of prison tattoo’s on the body of both Witbooi and Parsons taken after their arrest which showed the number 28.
Parson’s tattoo’s included crossed swords, a gun, a grotesque sketch of a naked headless female with legs spread open and shoulder stars showing his rank.
Investigating officer Sergeant Marlon Appolis said the significance of the number 28 showed that their role while in prison was to be the ‘wives’ of others.
He said: ‘To use the word of the street the 28’s take men from behind’.
Hannah was the daughter of magistrate Willem Cornelius and lawyer wife Anna, 56, who tragically drowned whilst swimming ten months after her murder.
Victim Hannah was a straight A’s student and in her second year at Stellenbosch University studying for a Bachelor of Arts when she was attacked and murdered.
Fellow student Mr Marsh broke down in tears as he told how they were hijacked and he was bundled into the boot while Hannah was held inside the car.
He said they had been for a few drinks and said he was going to use his skateboard to get home but Hannah insisted on driving him in case he was robbed.
Mr Marsh said when they pulled up the gang pounced threatening to stab Hannah to death with a sharpened screwdriver and him to death with a knife placed at his back.
The sexual assault Ms Cornelius suffered, a state pathologist told the Western Cape High Court ‘would have been a very painful experience to the person’
He described how they were driven to a suburb of Cape Town called Kraaifontein 11 miles from where they were hijacked in Stellenbosch and he was pulled from the car boot.
He said: ‘I lay down on the ground as they told me and put my head on a rock. I closed my eyes and I prayed. The two men were standing over me with bricks in their hands.
‘I lost consciousness and when I woke I was in horrible pain, everywhere pain. When I last heard Hannah talking her voice was very soft and I could tell she was scared’.
He managed to stagger to a nearby house covered in blood and raise the alarm.
Mr Marsh was so traumatised he never returned to his studies and is now deaf in one ear as a result of his injuries and vivid scars could be seen on his head as he gave evidence.
One of the men accused of the murder of Hannah had his confession made the day after his arrest read to the court and said the gang went into town ‘to see what they could get’.
Witbooi alleged the other three took Mr Marsh out the boot while he had a ‘smoke’ and into the bushes and said they told him they had tied him up and left him to be found.
He said he was ‘only after money’ and said after Mr Marsh was left for dead the gang drove off and later took Hannah into bushes but denied any part in her rape and murder.
Witbooi said that three others returned from the bushes after raping Hannah and said: ‘While we were driving Parsons said I had missed out on having had sex with her.
‘He said they had tied the girl up and that the workers would find her tomorrow’ he said.
The gang then high on drugs went on a robbery spree in the hijacked car robbing at least three women before the stolen car was spotted and a high speed police chase began.
Three were arrested after dumping the car and fleeing and the fourth was arrested later.
The latest crime figures in South Africa revealed that 56 people are murdered a day and that 110 people are raped a day and that there are 45 carjackings a day.
Follow Us on Instagram