This study examines the political uses of "conflict diamond" discourse in global debates about commodity certification and socially responsible mining in Zimbabwe. Engaging critical literature on "conflict-free" corporate branding initiatives, the study focuses on representations of conflict in Marange, in Zimbabwe's eastern highlands. In 2006, a diamond rush in Marange drew in tens of thousands of artisanal miners from across Zimbabwe as well as foreigners, and the government initiated military crackdowns in 2008. In a highly contested vote in 2009, the international government delegates who comprised the voting members in the Kimberley Process Certification System (KPCS) ruled that conflict in Marange did not meet the KPCS definitions of "conflict diamond." The study examines discourses of key stakeholders in the multinational diamond industry, human rights organizations, policymakers as well as artisanal miners in Zimbabwe between 2006 and 2014. The article argues that advocacies against diamond certification as well as advocacies favouring certification both tended to overlook the interests of artisanal miners, focusing narrowly on certain forms of conflict while associating artisanal mining with illicitness. The Marange case illustrates how conventional discourses on "conflict diamonds" not only obscure the complex nature of conflicts in contemporary capitalist accumulation processes; they also risk contributing to new forms of structural violence. This analysis highlights the need to pay careful attention to how global commodity certification discourses interrelate with political agendas at multiple scales. The study draws attention to dilemmas for geographers when portraying the interests of marginalized groups in-and affected by-the diamond mining sector.