Cerium occupies a paradoxical position in the rare earth supply chain: it is the most geologically abundant REE and commands one of the lowest market prices ($1/kg for 99.5% CeO2 in 2022–2024), yet it remains on the US Critical Minerals List and the EU Critical Raw Materials list because the refining and separation stage is overwhelmingly concentrated in China. An estimated 45,000 t of REO mineral concentrates were produced at Mountain Pass, CA in 2024 — enough to place the US as the world's second-largest mining country at 11.5% of global output — yet domestic compounds-and-metals output remained only 1,300 t in 2024, with 80% of refined product imported, primarily from Chinese sources (70% of US imports, 2020–23 average).

Cerium's dominant end use is catalysis: fluid catalytic cracking (FCC) catalysts for petroleum refining and automotive three-way catalytic converters together account for roughly 45% of Ce consumption. The element's oxygen storage capacity (OSC) and redox cycling between Ce³⁺ and Ce⁴⁺ are difficult to replicate with lower-cost materials. Glass polishing (CeO2 powder), specialty glass additives (UV blocking, decolorization), and metallurgical additions (mischmetall — nominally 65% Ce, 35% La — for cast iron and alloys) make up most of the remainder. Cerium benefits little from the EV-driven demand surge for magnet REEs (Nd, Pr, Dy, Tb), which has focused strategic attention on the heavier elements while leaving LREE (Ce, La) in structural surplus.

The structural driver of Ce's low price is the REE balance problem: cerium and lanthanum are produced in fixed proportions with higher-value Nd, Pr, Dy, and Tb that cannot be individually scaled. As demand for magnet REEs grows with EV adoption and wind turbine deployment, global Ce production rises in lockstep, depressing Ce prices regardless of Ce-specific demand. The US government's decision to include cerium in the FY2025 National Defense Stockpile acquisition targets (1,100 short tons) reflects supply-chain resilience concerns that go beyond price: the risk is not Ce scarcity but Chinese control over the downstream separation stage that transforms mine output into separated oxides, metals, and alloys.