Set against the ongoing corporate enclosure of West Africa's goldfields, A Ritual Geology tells the untold history of one of the world's oldest indigenous gold mining industries: Francophone West Africa's orpaillage. Establishing African miners as producers of subterranean knowledge, Robyn d'Avignon uncovers a dynamic "ritual geology" of techniques and cosmological engagements with the earth developed by agrarian residents of gold-bearing rocks in savanna West Africa. Colonial and corporate exploration geology in the region was built upon the ritual knowledge, gold discoveries, and skilled labor of African miners even as states racialized African mining as archaic, criminal, and pagan. Spanning the medieval and imperial past to the postcolonial present, d'Avignon weaves together long-term ethnographic and oral historical work in southeastern Senegal with archival and archeological evidence from Burkina Faso, Côte d'Ivoire, Guinea, and Mali. A Ritual Geology introduces transnational geological formations as a new regional framework for African studies, environmental history, and anthropology.