Kai Ryssdal: In South Africa today, authorities are trying to figure out what happened at a platinum mine outside Pretoria -- 34 people were killed, 80 injured, after police opened fire on a group of workers striking for higher wages.
From Johannesburg, Gretchen Wilson explains platinum prices are the root cause of the unrest.
Gretchen Wilson: Many South Africans say they're traumatized by video posted on news websites showing police shooting at a crowd of striking workers. Local talk radio stations are flooded with callers weeping, grieving for the dozens of lives lost. The shooting on a hilltop at the Lonmin Marikana mine is being called a national tragedy. But it's actually part of a bigger story.
The demand for South African metals, such as platinum, is driven mainly by foreign markets. Platinum is needed to make catalytic converters in cars, electrical equipment, and jewelry. But prices have been flat for the past five years, partly because platinum can be recycled. So mining companies here try to get by by hiring temporary workers and keeping the wages of unionized workers low.
Lesiba Seshoka is with the National Union of Mineworkers, which represents some workers at the Lonmin Marikana mine, but did not endorse the strike.
Lesiba Seshoka: The average wages of a miner -- the basic one -- is around five, six thousand.
That's around $700 a month. But because the number of mining jobs is limited and competition high, workers haven't had a lot of bargaining power in negotiations with mining companies.
Seshoka: Because mines can go to neighboring countries and get people that are quite cheap.
In the wake of the shooting, strikers at the Lonmin Marikana mine remain defiant. One told the BBC his resolve is even stronger.
Worker: We are not going to back to work right now -- they can beat us kill us, kick us and trample us with their feet.
Platinum prices are higher on global markets today, but unless there is a sustained increase low wages are likely to prevail in South Africa's mining industry.
In Johannesburg, I'm Gretchen Wilson for Marketplace.