LME cobalt settled at 39,140 USD/T on September 29, 2026, with a daily move of -500 USD/T (-1.26%) and a year-on-year gain of 11.83% [S1][S9]. The September 28 trading-economics print of 39,640 USD/T puts the standard-grade metal at roughly $17.95/lb on a straight conversion, while the Fastmarkets-cited cobalt hydroxide range sits at $22.00-$23.00/lb (bid-offer spread of $5/lb) [S1][S2].
That comparison is the single most-asked question on refinery desks in Q3 2026: which form is the cheaper cobalt unit, and where does the payable indicator fit? The short answer: at this point in the cycle, the intermediate (hydroxide) trades at a premium to the metal on a per-pound contained-cobalt basis, and that inversion is the central reason 2026 contract negotiations keep slipping into Q4 [S2][S3].
Price Levels on September 28-29, 2026
Cobalt hydroxide, min 30% Co, CIF China, holds a $22.00-$23.00/lb range with a $5/lb bid-offer gap, the published mid-point being $22.50/lb [S2]. Cobalt metal (CME cobalt standard-grade, in-warehouse Rotterdam) on September 29 reads 39,140 USD/T, which converts to roughly $17.75/lb at 2,204.62 lb/mt [S1][S9]. Trading-economics shows the same series at 39,640 USD/T one session earlier, equating to $17.98/lb [S1].
The 2026 H1 Benchmark Cobalt Institute reference values, released in late June 2026, list cobalt metal (Standard Rotterdam) at $28.78/lb (-$1.04/lb, -3.49% q-o-q) and cobalt sulphate at $26.23/lb [S5]. Those H1 prints anchor the historical comparison: between Q2 2026 and end-Q3 2026, Rotterdam metal dropped roughly 38% in $/lb terms (28.78 to 17.75) while hydroxide compressed more slowly [S1][S5]. For an engineer comparing quotes, the live $22.50/lb hydroxide versus $17.75-$17.98/lb metal is the actionable number on 2026-09-29.
Why Hydroxide Trades Above Metal: Payable Indicator Mechanics
The Fastmarkets payable indicator is a percentage value of the cobalt standard-grade price and is the most common pricing structure for cobalt hydroxide in the physical spot market [S4]. CME's Cobalt Hydroxide CIF China (Fastmarkets) futures contract settles against the inferred price, defined as the cobalt metal standard-grade low-end daily range multiplied by the payable indicator [S4]. The contract unit is 2,204.62 lb (one metric ton) of contained cobalt, traded in $/lb [S4].
When the live standard-grade metal sits at $17.75/lb and the inferred hydroxide settles at $22.50/lb, the implied payable is 127% of the standard-grade metal mid. That is structurally unusual: in most quarters of 2024-2025 the payable indicator ran between 75% and 90%, so hydroxide was the discount feedstock for Chinese refiners [S3]. The September 2026 inversion reflects DRC export-quota logistics (only ~8 kt/month of cobalt exiting the DRC) layered on top of an Indonesian HPAL output cut of 8.9% (49.2 kt revised to 44.8 kt for 2026) driven by sulphur cost inflation from $8,173/t to $16,586/t (+103%) [S5]. Cobalt is a key material in battery cathode precursors, superalloys, and cemented carbides, so any squeeze on intermediates ripples straight into metal powder feedstock pricing and downstream hard-metal tooling costs.
Historical Spread Trajectory: 2024-2026
In the 2024 Benchmark Mineral Intelligence note, cobalt hydroxide was published at a discount to metal, with weekly assessments introduced to capture faster-moving intermediate pricing [S2]. By March 25, 2026, metals-hub reported that CME cobalt metal had risen from roughly $10/lb (≈$22,000/mt) to $26/lb (≈$57,000/mt) while cobalt hydroxide moved from about $6/lb (≈$13,000/mt) into the same elevated band [S6].
Fastmarkets' Rotterdam standard-grade series showed hydroxide prices "jumping sharply before stabilizing" through 2025 and then "giving way to a sustained plateau into 2026" [S3]. On a $/lb contained-cobalt basis, the September 2026 reading of $22.50/lb hydroxide versus $17.75-$17.98/lb metal marks the first sustained inversion since the 2017-2018 DRC artisanal-export surge [S2][S3]. For spec writers, the practical takeaway is that any contract referencing hydroxide-as-percent-of-metal must now be reviewed: a 75-80% payable clause that was competitive in 2024 produces a windfall for the producer at 2026 spot.
Decision Matrix: Which Form to Source in Q4 2026
Four criteria decide whether a refiner or alloy producer should buy metal, hydroxide, or sulphate in Q4 2026, each with a number drawn from the research [S2][S4][S5].
Contained-cobalt cost: metal $17.75-$17.98/lb, hydroxide $22.00-$23.00/lb, sulphate $26.23/lb (H1 2026 reference) [S1][S2][S5]. Metal is the cheapest unit of contained cobalt on 2026-09-29, but it is not always the cheapest delivered unit because of freight, insurance, and assay premia. Refining fit: Platts assesses any-origin cobalt hydroxide at 30% cobalt content and 2-6% moisture [S7]. Supply availability: 2026 global mine supply is estimated at 225 kt (down from 267 kt in 2025), with DRC exports capped near 8 kt/month and Indonesia MHP cut 8.9% to 44.8 kt [S5]. Hydroxide availability is therefore the binding constraint, not metal cathode. Hedging instrument fit: CME lists separate Cobalt Metal (Fastmarkets) and Cobalt Hydroxide CIF China (Fastmarkets) futures, cash-settled against their own assessment with a high historical positive correlation but separate supply-demand drivers [S4]. A buyer hedging hydroxide exposure cannot perfectly cross-hedge with metal contracts in a 127% payable regime.
Use-case recommendation: if your plant takes metal directly into a vacuum-arc or VIM melt for superalloys, buy LME/CME metal at $17.75-$17.98/lb and avoid the 25-30% intermediate premium [S1][S5]. If your plant leaches into sulphate for cathode-precursor production, you are structurally a hydroxide buyer and the payable indicator (currently ≈127% of standard-grade metal) is the negotiating lever, not the absolute $/lb [S2][S4]. If you are a trader or cathode precursor off-taker without refining capacity, CME Cobalt Hydroxide CIF China (Fastmarkets) futures (globex COHU6) offer the cleanest $/lb exposure, 24-month forward curve, and 2,204.62 lb contract size [S4].
Supply-Side Drivers Reshaping the 2026 Spread
Three supply-side mechanics are why hydroxide is not collapsing toward metal even with the 38% Rotterdam correction since H1 [S1][S5]. First, DRC export quotas introduced in October 2025 left miners with only ~8 kt/month of exportable cobalt, and Q4 2025 quotas were fully drawn by end-April 2026, so backlog is just starting to clear [S5]. Second, Indonesia's weighted HPAL C1 cost (including by-product credits) jumped from a 64% other-costs / 36% sulphur split in 2025 to a 38% / 62% split in 2026, with elemental sulphur imports at 5.35 Mt/year (74% from the Middle East) exposed to Strait of Hormuz disruption [S5]. Third, Chinese imports of DRC intermediates collapsed in the January-September 2025 monthly series (lows of 0-1 kt against a 12-16 kt norm), and the recovery curve in 2026 is non-linear because of assaying irregularities and truck-availability constraints [S5].
Mine supply is forecast to grow into 2027 to 242 kt, with disruption allowance remaining high to reflect DRC and Indonesia uncertainty [S5]. 2026 cobalt demand is expected to grow 8.0% year-on-year, with EV batteries at 260.3 kt and superalloys at 14.9 kt leading the stack [S5]. The implication for spec-level buyers: any contract that prices hydroxide off a long-term trailing payable of 75-85% will produce a $4-$6/lb negative carry against 2026 spot, and the spread is more likely to compress from the hydroxide side (refinery restarts, DRC quota creep) than to widen further from the metal side. For a deeper breakdown of where the 260.3 kt EV demand is pulling cobalt, see the cobalt end-use demand 2026 working reference.
Reference Benchmarks and What to Track Next
Four price points are now actionable for Q4 2026 procurement [S1][S2][S4][S5][S7][S9]. LME cobalt cash settlement on the LME Cobalt page (US$ per tonne, last update 29 Sep 2026) [S9]. Trading-economics spot of 39,140 USD/T with a Q3 forecast of 39,667 USD/T and a 30.47% monthly decline flag [S1]. Fastmarkets cobalt hydroxide, min 30% Co, CIF China, $22.00-$23.00/lb with $5/lb bid-offer gap [S2]. S&P Platts Cobalt Metal 99.8% Mixed-Use Basket plus the cobalt hydroxide inferred assessment for any-origin 30% Co material [S7]. CME Cobalt Hydroxide CIF China (Fastmarkets) futures (COHU6) last update 29 Sep 2026 23:13 CT, providing the screen-quoted price for the inferred assessment [S4].
Until those flip, the September 2026 working assumption is metal at $17.75-$17.98/lb, hydroxide at $22.00-$23.00/lb, and sulphate at $26.23/lb (H1 reference), with the cost ranking metal < hydroxide < sulphate on a contained-cobalt basis [S1][S2][S5]. For buyers routing cobalt into metal material feedstocks or metal powder atomization lines, the metal-direct route is the cheapest unit in Q3 2026, but hydroxide remains the right hedge for the dominant EV precursor route.
Detailed specification references: metal curtain wall panel.