Cosatu general secretary Zwelinzima Vavi.
"They will be reinstated unconditionally and be paid R2 500 once off bonus," said North West provincial secretary Solly Phetoe.
Phetoe said the trade federation had been negotiating with Amplats and it had agreed to reinstate the workers.
Amplats fired 12 000 workers after they failed to appear for disciplinary hearing.
They had been on a wildcat strike since September 12, demanding to be paid a minimum of R16 000 per month.
"Be disciplined do not be provoked by any one," Phetoe said
"We have asked the police to remove all the people at the stadium, they wear red t-shirts, we do not have problem with them … we do not want people to disrupt our rally," he said to the applause of the crowd.
This was after it was reported that striking mineworkers wanted to disrupt the rally at the Olympia Park Stadium.
"Don't be afraid and don't allow to be provoked by anyone … We have permission for this march," he said.
Cosatu spokesperson Norman Mampane said no incidents were reported since Saturday morning.
"There have been no incidents. The police are aware of the situation and are ready to deal with it according to the law," he said.
The rally was organised to demand the reinstatement of dismissed workers and reclaim Rustenburg from what Cosatu called the "force of counter revolution".
The march went through Bethlehem Drive via Geelhout Park to the Olympia Park.
Dressed in red t-shirts, the marchers sang liberation songs through the 5km stretch.
In a memorandum prepared to be handed over to North West Premier Thandi Modise and representatives of employers, Cosatu said the march was being held in order to display anger at the poverty, the "slave wages" and the poor working and living conditions workers were experiencing since the dawn of democracy.
"The poor people of this country continue to be marginalised and subjected to sub-standard services and slave wages which continue to degrade their lives while the politicians and business executives continue to benefit from the rich economy this country possesses," the memorandum read.
The rally would be addressed by SA Communist Party secretary general Blade Nzimande, ANC secretary general Gwede Mantashe and Cosatu's secretary general Zwelinzima Vavi. – Sapa