East Rand Proprietary Mines (ERPM) is a 125-year-old underground gold mining operation on the Witwatersrand Basin at Boksburg, to the east of Johannesburg. The mine employed 3,850 people. It was the deepest mine in the world until 2008 at 3,585 metres depth, slightly more than the TauTona mine, also in South Africa, which was 3,581 metres at the time (in 2008 the TauTona mine completed a digging project that extended the depth of the mine by several hundred metres.)[1]
The mine closed in 2008. Historical gold production between 1896 and 2008 was 43 Moz at recovered gold grade of 8.1g/t (95% plant recovery).
A world class high grade gold deposit remains with existing in situ resources (SAMREC compliant) of 63 Moz, including;
- Measured & Indicated resource of 13.6 Moz at 6.7g/t Au
- Inferred resources of 50 Moz at 4.92 g/t Au.
The Cason mine dump was once the world’s highest manmade mountain. This dump is currently being recycled. It is now a shadow of its former self and will probably disappear in the near future.
Share of the East Rand Proprietary Mines Ltd, issued 19 October 1928
The ERPM engineered many mining techniques which are still in place today, including "Long Wall Mining". The mine also built the world's largest ice factory which produced up to 8,000t of ice daily to cool wall rock temperatures (50-60 deg Celsius).
Tucker, Rodney & Viljoen, Richard & J. Viljoen, Morris. (2016). A Review of the Witwatersrand Basin - The World's Greatest Goldfield. Episodes. 39. 105. 10.18814/epiiugs/2016/v39i2/95771.
