Exploitation of poorly paid black mine workers

To survive in the city, most of the characters in Mine Boy undertake precarious work—jobs that are either illegal or dangerous, and often both. The theme of precarious work is evident in Leah's illegal beer selling, which involves secrecy, police bribery, threat of jail time, and the need for violence to solve disputes that would otherwise be resolved by police. While the work Xuma undertakes in the mine is legal, the drive for profits and lack of worker rights allow for conditions that lead to lung sickness and unsafe working conditions.

In order to extract minute amounts of gold, the mine workers must move out truckloads of sand, which stand in great piles that Xuma sees on his first night out with Eliza. His first day at the mine involves creating the piles, toiling all day only to find that the piles appear to remain stagnant, not growing despite the constant backbreaking work of building them. Xuma's coworker tells him that eventually he will simply stop thinking about it. The mine dumps become symbolic of the futility that underprivileged men must make peace with, a process that renders them sheeplike and docile.

The gold mine doctor uses the simile "strong as an ox" to assess Xuma's capacity to continue working after he wounds his leg on the axle of the truck he is made to push alone.