Why are contemporary raw material supply chains structured as they are? This dissertation explores what shapes the supply chains of ‘critical materials’, metals and minerals which are of high economic importance and are at risk of supply shortage. The research focusses on cobalt, a metal mined mostly in the Democratic Republic of the Congo (DRC) and consumed mostly in the production of lithium-ion batteries in Asia, which are used in portable electronics and electric vehicles. Focussing on the 2007 to 2017 period, the aim of this research is to determine how the cobalt supply chain is structured and organised, how its structure and organisation have evolved temporally, how firms and states have responded to cobalt’s criticality, and how these responses have resulted in spatial and structural outcomes. The research thus aims to identify outcomes in the cobalt supply chain as well as the behaviours that have shaped those outcomes.

Research findings show that firms responded to cobalt’s criticality through foreign direct investment and vertical integration, thus altering the structure and geographies of the cobalt supply chain. Chinese firms, in particular, invested heavily in Congolese cobalt assets in order to secure access to cobalt units for Chinese downstream consumers and brought more production processes within the boundaries of the firm to capture value. These firm-level developments took place in the context of state-level responses to cobalt’s criticality. The research shows how a resource-holding state, the DRC, employed resource nationalist policies in order to capture value from the cobalt chain, while China, a resource-seeking state, created the conditions necessary for firms to acquire overseas cobalt assets and develop domestic capabilities in order to capture value.

The research is grounded in the literature on resource scarcity, global supply chains, and global production networks (GPNs). Empirically, this dissertation provides the first detailed analysis of the cobalt supply chain within economic geography and demonstrates the potential of the GPN and related frameworks, as well as more traditional theories of the state, firm and international trade, to contribute to the debate on critical materials and explain the structure and formation of their complex global networks. Conceptually, the dissertation makes a small contribution the research on supply chains by examining how the factors that make materials critical (supply risk and economic importance) have brought about reconfigurations of supply chains, influenced the tactics of key actors, and shaped the geographies of resource extraction, production, and consumption.