Johannesburg is known as the "City of Gold" among illegal workers in the nearby city of Zulu.

Johannesburg is known as the "City of Gold" among illegal workers in the nearby city of Zulu. Amid the strikes and employment in the South African nation, there has been a surge of illegal mining activity that has put lawful mining operators at risk.

The South African government estimated that there are about 8,000 illegal miners on the surface and 6,000 underground, which is equal to about 10 percent of the legal employees in the industry. 

Kenny Mashiane, 34, is one illegal miner who works in the South African mines. He said in a productive week with a rich seam of gold ore, he can make as much as 3,000 rand (about 311 Canadian dollars). Mashiane said he used to mine platinum for Lonmin Plc (LMI), the world's third-biggest producer of the metal. Currently, Goliath Gold Mining (GGM) Ltd. owns prospecting rights to the land where Mashiane mines.

Due to unemployment, poverty and large numbers of illegal immigrants, there has been a jump in unlawful mining, said Chamber of Mines, which represents producers including AngloGold Ashanti Ltd. (ANG),

Legal operators have fallen victim to the zama-zamas, or hustlers, who live and work in subterranean tunnels filled with robbery and other crimes, according to local police. Zama-zamas have been known to steal equipment and recruit fired laborers. More than 100 people have been sentenced this year for illegal mining, marking a rise in convictions. Not only do these hustlers put legal mining operations at risk, they also jeopardize the safety of the people living in neighboring towns.

"While we've certainly seen reports of illegal mining activities, the careful securing of entrances to our operational sites has thus far worked for us," David Noko, AngloGold's executive vice president for sustainability, told Bloomberg.

As a result of the illicit activity, legal mining companies are upping their security both along the perimeter and inside shafts. South African mines don't need any further disruption, making equipment maintenance software and remote equipment monitoring - which prevents unwanted downtime - a must. 

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