The study of the impacts of new mining projects in Africa is generally set in a normative debate about their possible contribution to development, which leads to a representation of African societies as divided between beneficiaries and victims of foreign investments. Based on research in the Congolese copperbelt, this article aims to examine in more detail the inequalities generated by the recent mining boom by taking the processes of labour market segmentation as a starting point. It shows that the labour market in the mining sector has progressively been organized along three intersecting lines that divide it: the first is between employment in industrial and artisanal mining companies, the second is between jobs for mining or subcontracting companies and the third is between jobs for expatriates, Congolese skilled workers and local unskilled workers. Far from simply reflecting existing social inequalities, the labour market has been actively involved in their creation, and its control has caused growing tensions in the Congolese copperbelt region. Although largely neglected in the literature on extractive industries, processes of labour market segmentation are key to making sense of the impacts of mining investments on the shape of societies in the global South.