A shale quarry at the centre of a gold rush in southern KwaZulu-Natal has been declared off-limits as police struggle to fend off bandits.

Riot police have been deployed to KwaMachi, outside Harding, to protect the quarry from hundreds who descended on the site 10 days ago.

Economic development, tourism and environmental
affairs MEC Sihle Zikalala has declared the site a no-go area.

"We must ensure that the area is enclosed for proper investigation by the department of mineral resources," he said.

Zikalala was speaking at a stakeholder engagement session in Harding on Sunday.

"What we have are stones which look like gold. We need to make sure that no one can access that area and the police will ensure that."

His call comes after several people were injured in rockfalls at the quarry. Clashes between rival miners have also been recorded.

Zikalala said the discovery had caused a surge in truancy in local schools, with children ditching class to mine at the quarry.

The police's Ugu district cluster commander Brigadier Bongani Sibiya said officers had been hard-pressed to keep people off the site.

He said miners had damaged lengths of razor wire, as well as stolen wheels from the trailers that deployed them.

"One of our razor wire trailers was overturned down the hillside by these miners.

"We are doing all that is possible to secure the site," Sibiya said.

Nqobile Khanyile, the spokeswoman for the department of mineral resources, said test results on the site were still inconclusive.

"The department, together with the Council for Geoscience, have already taken samples of the rock found and have taken it for lab testing, the results of which will be available in a few weeks," she said.

"The minister of mineral resources is empowered in terms of section 50 of the MPRDA [Mineral and Petroleum Resources Development Act] to investigate the occurrence of or to establish if any mineral or geological formation occurs on or under land, as well as the nature and extent of mineral resources."