Why were the gold deposits of the Witwatersrand difficult and expensive to mine?

The gold deposits of the Witwatersrand were difficult and expensive to mine primarily due to the specific geological and economic conditions of the region. Although the gold was abundant, the ore was extremely low-grade, meaning that vast quantities of rock had to be processed to extract even small amounts of gold.12

Furthermore, the gold-bearing reefs were located at great depths, eventually extending thousands of feet underground, which required intensive, deep-level mining operations. These factors necessitated significant capital investment and advanced technology for crushing, refining, and processing the ore, making it impossible for individual prospectors to work the fields effectively.123

To maintain profitability against an internationally fixed price for gold, the industry underwent rapid consolidation into large mining corporations. These companies sought to reduce costs by rationalizing production and suppressing labor expenses, which led to the establishment of a system that relied heavily on low-paid migrant labor.21