Thirty-three men were arrested for illegal mining at Sibanye Gold Mine in the West Rand on Wednesday, the Hawks said.
Mine security guards went underground in the early hours of Wednesday, found the men, brought them to surface and handed them over to the police, Captain Paul Ramaloko said.
"They were found with mining equipment, 50 kg of gold bearing material and a substantial amount of cash," he said.
The men were expected to appear in the Westonaria Magistrate's Court on Thursday.