Rhenium

What Is Rhenium

Rhenium is element 75 — the rarest naturally occurring stable metal in the earth's crust, discovered in 1925 and named after the Rhine river. It has the second-highest melting point of any element at 3,186 degrees Celsius, exceeded only by tungsten. It does not occur in concentrated ore deposits of its own. It is found in trace quantities in molybdenite (the primary molybdenum mineral, molybdenum disulfide) at concentrations of typically 0.001–0.002% by weight — and molybdenite itself is primarily recovered as a byproduct of copper mining. Rhenium therefore sits two steps removed from any primary mining decision: it is a byproduct of a byproduct. You cannot mine rhenium. You can only recover it when copper and molybdenum production makes it available.

Global rhenium production runs at approximately 60 tonnes per year — one of the smallest commodity markets on earth by production volume. At that scale, the entire annual global output of rhenium would fit inside a single standard shipping container with room to spare. The scarcity is not geological in the conventional sense — the metal exists in copper and molybdenum deposits globally — but it is structural and permanent. The byproduct recovery ratio is fixed by the ore chemistry. More rhenium supply requires more copper mining, more molybdenum byproduct, and more rhenium recovery infrastructure at the roasting stage. None of those decisions are made on the basis of rhenium economics.

Rhenium is not scarce because the ore is rare. It is scarce because nobody mines for it.

What Rhenium Does

The jet engine application defines rhenium's strategic importance and accounts for approximately 80% of global consumption. Rhenium is added to single-crystal nickel superalloys (precision-engineered metal compounds grown as a single continuous crystal rather than a polycrystalline structure — a manufacturing process that eliminates grain boundaries where structural failure initiates at high temperature) used in the highest-temperature sections of jet engine turbine blades and vanes. At concentrations of 3–6% by weight, rhenium dramatically increases the creep resistance (resistance to slow permanent deformation under sustained stress at high temperature — the failure mode that limits turbine blade life) of the alloy, allowing engine operating temperatures 50–100 degrees Celsius higher than would otherwise be possible.

Higher operating temperatures mean higher thermodynamic efficiency — the fundamental engineering relationship that has driven jet engine improvement for decades. Every generation of commercial and military turbofan engine since the 1980s has used rhenium in its highest-temperature turbine stages. The CFM LEAP engine powering the Boeing 737 MAX and Airbus A320neo, the GE9X on the 777X, the Rolls-Royce Trent XWB on the A350 — all contain rhenium. Military turbofans for the F-22, F-35, and their international equivalents contain rhenium. There is no substitute that delivers equivalent performance at current engine operating temperatures. The aerospace industry has investigated alternatives for decades and has not found one.

A minor but growing application is rhenium-based catalysts for petroleum reforming (the refinery process that converts low-octane naphtha into high-octane gasoline components) where rhenium improves catalyst stability and selectivity. This application consumes approximately 10–15% of global production.

Rhenium makes jet engines work at the temperatures that define modern aviation. Nothing else does.

The Molybdenum Shadow

The supply chain runs as follows. Copper ore is mined at large-scale porphyry copper deposits (low-grade, large-volume copper deposits formed by volcanic activity — the geological type that dominates Chile and Peru). Molybdenum is recovered as a byproduct of copper concentration, producing molybdenite concentrate. That concentrate is roasted (heated in air to convert molybdenum sulfide to molybdenum oxide) — and it is during roasting that rhenium, which concentrates in the molybdenite, is volatilized and can be captured from the roaster gases. Not all molybdenum roasters have rhenium recovery systems installed. Where they do, rhenium is recovered as ammonium perrhenate (APR — the primary commercial form of rhenium, a water-soluble salt that is the starting material for most downstream rhenium processing) and sold or processed further.

The capture rate is therefore not 100% even where the chemistry makes recovery possible. Older or lower-capacity roasters may not have the recovery infrastructure to capture rhenium from the gas stream. Expanding global rhenium supply requires not just more copper and molybdenum production but also expanded roaster recovery infrastructure — and that infrastructure investment must be justified by rhenium economics alone, since the molybdenum roasting decision is made independently.

Chile's copper mines — particularly Freeport-McMoRan's Cerro Verde, Codelco's El Teniente and Chuquicamata, and Anglo American's Los Bronces — are the world's dominant rhenium sources precisely because they produce large volumes of molybdenum-rich copper concentrate with high rhenium content per tonne of molybdenite. Chile accounts for approximately 52% of global rhenium production. Kazakhstan and the United States account for most of the remainder.

China has been aggressively building rhenium inventory since 2023, driven by its domestic aerospace expansion — the COMAC C919 commercial aircraft program and the continued development of Chinese military jet engines all require rhenium for turbine blades. Chinese demand growth against a fixed global supply contributed materially to the 193% price increase since January 2025.

The byproduct chain is two steps long. The jet engine industry sits at the end of it with no ability to influence either step.

Where It Comes From

Chile is the dominant source, accounting for approximately 52% of global rhenium production through its large copper-molybdenum porphyry operations. Codelco's El Teniente mine is one of the largest rhenium-producing operations in the world, integrated into its molybdenum byproduct recovery infrastructure. Freeport-McMoRan's Cerro Verde operation in Peru (which shares the same geological type) also contributes significant volumes.

Kazakhstan is the second-largest producer, recovering rhenium from its Zhezkazgan copper deposit — which has unusually high rhenium content relative to most copper ores globally. Kazakhstan's production serves Russian and Chinese customers primarily and has been less accessible to Western buyers in recent years.

The United States has minor rhenium production from molybdenum operations in Colorado and from copper mines in Arizona, but domestic production covers a small fraction of US aerospace demand. The gap is filled by Chilean imports primarily.

Russia historically produced significant rhenium from its Far East copper operations, but sanctions have complicated Western access. China has domestic production from its molybdenum operations in Shaanxi and Henan provinces, but domestic production is insufficient for its rapidly growing aerospace demand — hence Chinese procurement from Chilean and Kazakh sources.

The refining and downstream processing infrastructure for converting APR into rhenium metal, rhenium alloy powder, and superalloy additions is distributed across the United States, Germany, and the UK, with specialty materials companies performing the conversion for aerospace customers.

The Market Structure

Rhenium is priced as a Western retail benchmark with no liquid exchange contract. The Strategic Metals Invest benchmark for rhenium metal sits at $7,283.30 per kilogram as of May 20, 2026 — up 53% year to date, up 193% since January 2025, and up 326% since January 2020.

The price appreciation reflects three concurrent forces. First, commercial aviation recovery: aircraft production at Boeing and Airbus accelerated after pandemic-era cuts, driving new engine orders and rhenium procurement for turbine blade production. Engine manufacturers including GE Aerospace, Rolls-Royce, and Pratt & Whitney are all ramping production against order backlogs that stretch years. Second, Chinese aerospace demand: China's COMAC C919 program and military jet engine development have added a new, large, price-insensitive buyer to a market that was previously dominated by Western aerospace programs. Third, supply inelasticity: rhenium production has not increased meaningfully because copper and molybdenum production decisions are not driven by rhenium economics.

The market is small enough that procurement cycles from individual aerospace programs move the price. When GE Aerospace or Rolls-Royce books a major turbine blade production run, rhenium spot prices respond. When Chinese state aerospace procurement accelerates, the same dynamic occurs. At 60 tonnes of annual supply, any demand increment is significant.

Why It's on This List

ScarceEarth covers rhenium because it is the most extreme available example of byproduct supply inelasticity — a metal whose price has risen 326% since 2020 and whose supply has no mechanism to respond to that price signal.

Rhenium cannot be mined. It can only be recovered as a secondary byproduct of copper and molybdenum operations whose economics are entirely independent of rhenium. A rhenium price of $7,283 per kilogram does not incentivize building new rhenium recovery capacity the way a lithium price spike incentivizes new lithium mines. It might, at the margin, incentivize installing rhenium recovery systems on existing molybdenum roasters that currently lack them — and that is approximately the limit of the supply response available.

The defense implication runs directly through the aerospace supply chain. Every military jet engine — F-22, F-35, B-21 bomber engines, naval aircraft — contains rhenium in its highest-temperature turbine stages. The same supply chain concerns that apply to rare earth magnets and tungsten apply to rhenium, though rhenium has received less policy attention because its primary supply comes from Chile rather than China. Chile is an ally and a stable jurisdiction. But the supply is still thin, the recovery infrastructure is still limited, and the 60-tonne annual production figure leaves very little buffer if demand accelerates further or a major copper operation is disrupted.