Two neighbouring republics, with a common history and culture, followed very different paths of development in the second half of the nineteenth century. Extraordinary mineral wealth was discovered during this period in the South African Republic (ZAR), the neighbour where political and economic stability was fragile compared with the Republic of the Orange Free State (OFS). We connect these divergent development paths to the literature on the resource curse, especially the recent literature on the conditional resource curse where the quality of the institutional structure plays a crucial role in the outcomes of a large resource discovery. By introducing a new objective measure for the quality of institutions, namely the accuracy of boundaries on maps, we provide evidence of the institutional quality in the ZAR prior to the discovery of gold on the Witwatersrand. The statistical technique that we use, Procrustes analysis, is an innovation in economic analysis. The evidence supports Acemoglu and Robinson’s account of the development path in the ZAR, and the later Union of South Africa, as compromised by the conditional resource curse.