The protesters faced charges of public violence, Zululand Observer reported.
The 57 accused had been arrested during a riot on the highway between Gingindlovu and Mtunzini, where one man died.
Protesters had been up in arms over the alleged lack of cooperation from the Tronox Fairbreeze mine.
The Institute for Security Studies (ISS) said although community protest action in South Africa remained stable over the past five years, the level of violence that accompanied them has increased.
Last week, a reporter and photographer from Beeld newspaper were hijacked by a group of protesters in Majakaneng during a violent protest.
According to photographer Deaan Vivier, they were forced out of their vehicle and threatened with knives.
Both were shaken up but unharmed.
Senior ISS researcher Johan Burger said the violence had, according to police, escalated by 90%.
“This indicates violence is becoming uniquely South African,” he said.
“The possible reasons for the violent acts include the inequality gap among citizens, the high levels of frustrations, which also contributed to the recent looting of foreign nationals’ shops, and communities feeling neglected due to lack of service delivery in some areas.”
Burger said about 11 000 protests has been recorded yearly in the past five years.
– Caxton News Service