An Introduction to Aluminium Markets

A complete, beginner-friendly map of how aluminium is mined, refined, smelted, traded, and priced - and who does each part This is meant to stand on its own as a first introduction to the aluminium market as a whole. It assumes no prior knowledge and builds in order: first the physical metal and the chain of businesses that handle it, then the units and contracts the market is quoted in, then the financial market layered on top, then the participants and the desks that operate it, and finally the forces cost curves, geopolitics, history - that move the whole thing. Read it top to bottom the first time; later sections lean on earlier vocabulary. It is a structural explainer, not a price call. (A note on spelling: this uses "aluminium," the international and London Metal Exchange convention; "aluminum" is the same metal.) The whole market in one paragraph. Aluminium is the lightweight structural metal, and unusually it is made in two upstream stages and then conjured out of electricity. It starts as bauxite ore, which is refined into a white powder called alumina (aluminium oxide), which is then smelted into metal by passing a huge electric current through it. That smelting step is so power-hungry that aluminium is often described as "solidified electricity," and it is why smelters cluster where power is cheap and why China, with vast coal power and state policy, now makes close to 60% of the world's metal. The finished metal is rolled, extruded, and cast into transport, construction, packaging, and electrical goods. On top of this physical chain sits a financial market on the London Metal Exchange and other venues, where producers and consumers hedge price risk and traders profit from gaps in time, place, and form. Because the metal is abundant in the ground but expensive in energy to extract, aluminium's price is driven less by ore scarcity than by power costs, Chinese supply policy, and where the metal physically sits. The value chain at a glance:

Upstream

Midstream

Downstream

Bauxite mining

~4 t ore per t of metal

Alumina refining

Bayer process, alumina

Smelting

Hall-Héroult, ~14 MWh/t

Casting

primary metal, 99.7%

Semi-fabrication rolling, extrusion

Recycled scrap (~5% of energy)

End use

China ~55-60% of demand

The aluminium value chain: from bauxite to end use, with recycled scrap re-entering supply.

What aluminium is and why its market exists

Aluminium is light (about a third the density of steel or copper), conducts electricity and heat well, resists corrosion because it forms its own protective oxide skin, and is easy to roll, extrude, and recycle. Those properties make it the default where weight matters: vehicles, aircraft, drink cans, building facades, power lines, and heat sinks. A paradox sits at the centre of the market. Aluminium is the most abundant metal in the Earth's crust, so the raw material is not scarce. What is expensive is the energy to separate the metal from its ore. That single fact - cheap rock, costly electricity - shapes the entire industry and is the main thing that distinguishes aluminium from a metal like copper, where the ore itself is the scarce, price-setting constraint. Where the demand comes from, roughly in order: transport (cars, trucks, and aircraft, where aluminium replaces heavier steel to cut weight and, in electric vehicles, to offset battery mass), construction (window frames, facades, structural sections), packaging (drink cans and foil), electrical (power cables and busbars, where aluminium often substitutes for more expensive copper), and machinery and consumer durables. A useful idea is lightweighting: as fueleconomy and emissions rules tighten and as EVs spread, each vehicle tends to use more aluminium over time, a slow structural tailwind for demand. Two facts shape everything else and recur throughout: Supply is set by energy, not ore. Smelters are, in effect, electricity buyers that happen to produce metal; the cheapest power wins, and that is why production sits in hydro regions (Canada, Norway, Iceland), gas-rich Gulf states, and coal-heavy China.

China dominates, and has capped itself. China makes close to 60% of the world's primary aluminium and consumes a similar share, but it has imposed a roughly 45 million tonne ceiling on its own smelting capacity, which is now the single most important structural feature of the global market. A natural ceiling on demand is substitution. Aluminium competes with steel in vehicles, with copper in electrical cable (aluminium wins when copper is expensive, because it is far cheaper per unit of conductivity by weight, though bulkier), and with glass and plastic in packaging. These trade-offs cap how far the price can run before buyers switch.

The aluminium value chain (the physical spine)

Aluminium moves through a pipeline of distinct businesses, each buying from the one before. Unlike copper, the upstream has two separate chemical stages (ore to alumina, then alumina to metal), and "the price of aluminium" is really a family of related prices: bauxite, alumina, and primary metal.

Bauxite mining

Aluminium begins as bauxite, a reddish ore named after the village of Les Baux in France. It is mined in shallow open pits, often simply scraped from near the surface, and it takes roughly four tonnes of bauxite to make one tonne of finished metal. Mining is geographically concentrated: Australia and Guinea are the two largest producers by a wide margin (Guinea has surged to rival or overtake Australia), followed by China, Brazil, and India. Much of Guinea's ore is shipped raw, as "direct shipping ore," because the country has little refining capacity of its own. Two features matter downstream. First, China has limited high-grade bauxite of its own and imports well over half its needs, much of it from Guinea, which makes that single trade route strategically important. Second, bauxite mining and the refining that follows generate "red mud," a caustic waste that is a significant environmental and disposal challenge.

Alumina refining: the Bayer process

Bauxite is not smelted directly. It is first refined into alumina (aluminium oxide, a white powder) using the Bayer process, which dissolves the aluminium content in hot caustic soda and precipitates out purified alumina. It takes roughly two tonnes of bauxite to make one tonne of alumina, and this stage uses a lot of heat (typically from gas or coal), so it is energy-intensive in its own right, though far less electricity-hungry than smelting. Alumina is a traded commodity with its own price, quoted as a percentage of the metal price (historically averaging around 16-17% of the aluminium price, though it swings well outside that band during alumina shortages). China is by far the largest alumina refiner, at roughly 60% of world output, with Australia a distant second. Because alumina sits between a concentrated set of refineries and the smelters that need it, a refinery outage can spike the alumina price and squeeze smelter margins, independently of what the metal itself is doing.

Smelting: the Hall-Héroult process

This is the defining step. Alumina is dissolved in a molten bath and a powerful electric current is passed through it, splitting the alumina into pure aluminium metal and oxygen (the HallHéroult process, unchanged in principle since 1886). It takes roughly two tonnes of alumina to make one tonne of metal, and the electricity required is enormous: about 13 to 15 megawatthours per tonne, enough that a single large smelter can consume as much power as a small city. The consequences run through the whole market: Power is the dominant cost, typically around 30-40% of the cash cost of metal, so a smelter's competitiveness is mostly its power contract. Producers negotiate long-term deals (often 1020 years) and locate where electricity is cheap and reliable. Smelters cannot easily switch off. The molten bath (the "potline") will freeze and be ruined if power is cut for long, so smelters run as constant baseload and are vulnerable to power shortages, as China's hydro-dependent Yunnan province has shown during droughts. It is the carbon story. Most of aluminium's large carbon footprint comes from the electricity used here; coal-powered smelting is very carbon-intensive, which is why "green" (hydro- or renewable-powered) metal commands a premium and why carbon policy bears directly on the industry. Smelting also consumes carbon anodes (which are slowly burned away and must be replaced) and is the reason the industry is sometimes called a business of turning electricity into a storable, shippable form.

Casting and primary products

Molten metal from the smelter is cast into standard shapes: ingots and "sows" for remelting, billets for extrusion, slabs for rolling, and T-bars. The benchmark traded grade is P1020, which is 99.7% pure aluminium (the name refers to its impurity limits). When you see an exchange price, it refers to this primary, standard-grade metal.

Semi-fabrication

Primary (and recycled) metal goes to fabricators who turn it into semi-finished products, "semis": rolling produces sheet, plate, and foil (for cans, packaging, and car body panels); extrusion pushes heated billet through dies to make profiles (window frames, structural sections, heat sinks); and casting and wire-drawing make engine parts and electrical conductor. These semis then feed final goods.

End use

The largest end markets are transport and construction, followed by packaging, electrical, and machinery. Demand here ultimately validates or rejects the price, and Chinese demand in particular - tied to its property sector, manufacturing, and exports - is large enough that shifts in Chinese construction or stimulus move the global balance.

Recycling: secondary aluminium

This is one of aluminium's defining advantages. Remelting scrap into "secondary" aluminium uses only about 5% of the energy of making primary metal from ore, because you skip the entire bauxite-alumina-smelting chain and simply melt and recast. The metal does not degrade in

recycling, so it can be reused indefinitely; drink cans are a near-closed loop, and end-of-life vehicles and buildings are major scrap sources. Secondary metal is a large and growing share of supply - the United States now sources roughly three-quarters of its aluminium from scrap, and China is rapidly building secondary capacity. Because recycling avoids the energyintensive steps, it both lowers cost and sharply cuts emissions, which makes scrap availability an increasingly important variable for the whole market.

How aluminium is measured and quoted (units, grades, contracts)

A beginner needs the units before the markets make sense. Weight and price units. The London Metal Exchange (LME) quotes aluminium in US dollars per metric tonne. (One tonne is 2,204.62 lb.) The US market also references prices in cents per pound for some purposes, but the global benchmark is the LME dollar-per-tonne figure. Grade and deliverable form. The LME's benchmark is P1020A primary aluminium, 99.7% pure, to a registered list of brands and shapes. There is also a separate, smaller LME contract for aluminium alloy (used in castings, e.g. for autos), and SHFE (Shanghai) trades a Chinese primary contract. The point to remember is that the exchange trades a defined standard primary metal, not scrap or alloy, so secondary and alloy markets trade at their own differentials. Three priced commodities, not one. Because the chain has two upstream stages, there are three distinct markets to watch: bauxite (mostly sold on contracts and assessed indices, with no deep futures market), alumina (assessed by a published index, the API, and now with futures on the LME and in Shanghai), and primary aluminium (the liquid, LME-benchmarked metal). The relationships between them, especially the alumina-to-aluminium price ratio, are themselves traded and analysed. Contract size. One LME aluminium lot is 25 tonnes, the building block of position sizes.

The financial market (layered on top of the physical)

Everything above is the physical market. On top sits a financial market where far more "aluminium" trades than is ever delivered, and the relationship between the two is where most trading happens.

The exchanges and price discovery

LME (London Metal Exchange): the global benchmark, in dollars per tonne, with a worldwide network of approved warehouses and a date structure built around physical delivery. Its key references are the cash (spot) and three-month ("3M") prices, partly discovered in open-outcry sessions ("the Ring"). SHFE (Shanghai Futures Exchange): the Chinese benchmark, reflecting domestic conditions, plus a bonded-market premium for metal held pre-customs. CME: trades an LME-linked contract and, importantly, the US Midwest premium as a separate contract (see 4.4).

Alumina futures: newly introduced on the LME and in Shanghai, letting refiners and smelters hedge the alumina price directly rather than only the metal. As with other metals, there is not one single world price but a benchmark plus regional prices, and the gaps between them carry information about tariffs and regional tightness.

The forward curve: contango and backwardation

A futures curve plots the price for delivery at different future dates. Contango means later delivery costs more than near delivery (the "normal" state, roughly the cost of storing and financing metal). Backwardation means near delivery costs more (a sign of near-term tightness, when buyers pay up for metal now). The front of the curve (cash versus 3M) is the most sensitive gauge. Aluminium is the metal where the contango trade became most famous. When the curve is in steep contango and financing is cheap, a trader can buy metal now, sell it forward at a higher price, and pocket the difference for simply storing it - the "stock-financing trade." After 2008, this locked up enormous tonnages of aluminium in warehouses (more on the consequences in 4.3 and 11).

Warehouses, warrants, and the queue saga

Exchange warehouses hold the metal that backs the contracts. On-warrant stock is metal available to the market; cancelled warrants are metal earmarked for withdrawal. What you watch is whether stock is building or drawing, and where. Aluminium produced the most notorious warehousing episode in modern metals. In the early 2010s, the combination of cheap money, a steep contango, and the stock-financing trade drew huge volumes of metal into LME warehouses, especially in Detroit (operated by a Goldman Sachs-owned company) and Vlissingen (operated by a Glencore-owned company). Because warehouses earn rent on stored metal, long load-out queues built up - at times over a year to physically retrieve metal - which inflated the regional premium consumers had to pay to actually get their aluminium, even while the LME headline price was low. The episode triggered lawsuits and a series of LME rule changes on load-out rates, and it remains the textbook example of how the plumbing of a metal market can become a trade and a distortion in its own right.

Premiums

On top of the exchange price, a physical buyer pays a regional premium to get metal delivered to a specific place in a specific form, and for aluminium these premiums are unusually large and closely watched. The main ones are the US Midwest premium (large, and heavily shaped by US import tariffs), the MJP (Main Japanese Port, negotiated quarterly for Asian supply), and European duty-paid and duty-unpaid premiums (Rotterdam). The all-in cost of metal to a consumer is the LME price plus the relevant premium, and because the US premium embeds the tariff, it can move sharply on trade policy alone.

OTC, swaps, and hedging

A large over-the-counter market, run by banks and merchants, lets participants customise. Hedging is what most of it is for, and it explains why the paper market dwarfs the physical:

Producer (smelter) hedge: a smelter worried about falling prices sells futures or swaps against metal it will produce, locking in a price. Consumer hedge: a carmaker, can maker, or aerospace firm worried about rising input costs buys futures or swaps to fix its purchase cost. Aluminium consumers are some of the most active hedgers in any metal, because aluminium is a large, visible input cost for beverage, automotive, and aerospace companies. Many also hedge the regional premium separately (the CME Midwest premium contract exists precisely for this), since the premium can move independently of the LME price.

Options

Beyond futures and swaps, options let participants shape risk asymmetrically: a producer can buy a put (a price floor) while keeping upside; a consumer can buy a call (a cost cap). Options also let traders express views on volatility itself. They are a standard tool on derivatives desks and in structured hedges, though smaller and less liquid than the futures.

Who's in the market (a participant taxonomy)

It helps to sort participants two ways: by why they are there, then by who they actually are.

By motive

Hedgers, producers: smelters and refiners reducing the risk of falling prices on output they will sell. Hedgers, consumers: carmakers, can and packaging makers, aerospace, and construction firms reducing the risk of rising prices on metal they must buy. Merchants and arbitrageurs: trading houses that take ownership of physical metal and profit from gaps in time (the curve), space (regional premiums), and form (ingot versus alloy, primary versus scrap). Financial participants and speculators: funds and investors taking price or relative-value positions, providing liquidity and absorbing risk that hedgers want to shed. Data and infrastructure: exchanges, warehouses, assayers, statistical bodies, and pricereporting agencies that make the rest function.

The named players

Integrated producers and smelters. The largest is China Hongqiao, the world's biggest aluminium producer, alongside other Chinese majors Chinalco (Chalco) and the hydropowerbased Yunnan Aluminium. Outside China, the major names are Rio Tinto (which absorbed the old Alcan), Alcoa, Norsk Hydro (Norway), Rusal (Russia, the largest producer outside China), Emirates Global Aluminium (EGA, in the UAE), Alba (Bahrain), Ma'aden (Saudi Arabia), South32 and Vedanta and Hindalco (the last via Novelis, a global leader in rolled and recycled products), and Century Aluminum in the US. Bauxite and alumina. Australia's mines (Rio Tinto, Alcoa, South32), Guinea's large operations, and China's Chalco dominate the upstream; China is the dominant alumina refiner.

Trading houses. Glencore is a major force in physical aluminium (historically a large marketer of Rusal's metal), alongside Trafigura and other merchants; their edge is logistics, warehousing relationships, and the balance sheet to carry and finance metal. Consumers worth knowing. Automakers, Boeing and Airbus in aerospace, beverage-can makers (such as Ball, Crown, and Ardagh), and large construction and electrical buyers. The data ecosystem. The IAI (International Aluminium Institute, the standard production data), USGS (mine and refinery data), consultancies (CRU, Wood Mackenzie, Harbor Aluminum, CM Group), and price-reporting agencies (Fastmarkets, S&P Global Platts, Argus) for premiums and the alumina index. As always, take a figure from the issuing body's own release rather than an aggregator.

Trading desks and hedge funds (the operating seats)

This is where the financial market is actually run, and the kinds of seat differ. Bank commodity desks. Inside a bank's markets division, a base-metals desk quotes two-sided prices to clients in futures, options, and OTC swaps and manages the resulting risk (flow / market-making); builds bespoke hedges for producers and consumers (structuring); and, less than before, finances inventory. Post-2008 regulation pushed most banks largely out of owning physical metal and out of pure proprietary risk-taking. Merchant trading. The trading houses run physical books: they own real metal, hedge the flatprice risk on the exchange, and keep the basis (premiums, spreads, freight) as their edge. In aluminium this is as much a warehousing-and-financing business as a market-view business, which is exactly why the houses sat at the centre of the warehouse-queue era. Hedge funds and specialist funds. Discretionary macro and commodity funds take views from fundamentals; CTAs and trend-followers trade futures on price momentum and can amplify moves; multi-strategy "pod shops" run many small teams under tight risk limits; and quant funds trade metals statistically, including cross-exchange and curve relative-value. The canonical trades: Directional (flat price): bet aluminium rises or falls. Calendar spreads and the financing trade: trade contango versus backwardation; the physical version stores metal to capture a steep contango (the trade that defined the warehouse era). Location and premium arbitrage: trade regional premiums (Midwest, MJP, European) and move metal when a spread overshoots freight plus tariff plus financing. Alumina-to-aluminium and alloy spreads: trade the ratio between alumina and metal, or between primary and alloy. Hedging is the connective theme: a physical trader who buys metal sells futures to neutralise flat-price risk and keep only the basis it has a view on. On the exchange side, futures positions require margin and are marked to market daily, so even a well-hedged book needs cash to fund margin calls when prices swing.

How everything interacts (the causal chain)

The mental model that ties the sections together: Power prices set smelter economics, which (alongside China's capacity cap) set primary supply. Upstream, bauxite and alumina availability set the alumina price, which feeds smelter margins independently of the metal price. Primary supply, plus a large and growing stream of recycled secondary metal, meets demand (China is close to 60%, plus transport-led lightweighting and a slower rest-of-world). The balance (supply minus demand) sets how many days of consumption the available inventory can cover, which drives the curve (contango versus backwardation). But on top of all this, three things specific to aluminium frequently dominate: the price of power (the swing input), China's supply policy (the 45 Mt cap and periodic smelter curtailments), and where the metal physically sits (regional premiums and tariffs). When the market looks confusing, the resolution is usually power, policy, or location rather than the headline tonnage balance.

Reading the market (balance and the cost-curve lens)

When you see a supply-demand balance for aluminium, read it with three aluminium-specific lenses: The cost curve is a power curve. The marginal tonne of aluminium is set by the highest-cost smelter still running, and its cost is mostly electricity. So when you ask "what price is sustainable," you are really asking about the power cost of the marginal (often Chinese coalpowered or European) smelter. China's cap is the supply ceiling. China makes close to 60% of the metal but has self-imposed a roughly 45 million tonne limit on capacity. As Chinese output presses against that ceiling, the usual source of cheap incremental supply is closing off, which is why the market has shifted from chronic surplus toward potential tightness. Watch alumina and secondary metal. A tight alumina market can squeeze smelter margins even when metal looks balanced, and the rising share of recycled secondary metal is an increasingly large swing factor in total supply. As with copper, statistical balances are apparent balances that can miss unreported or offexchange inventory, and they swing on demand revisions, so they are better carried as a range than a point.

Prices, cycles, and the long arc

What sets the price, by horizon: Near term (days to a quarter): power and macro and policy - energy prices, the dollar, growth, tariffs, and the regional premiums. The all-in cost to a consumer can move on tariffs alone. Medium term (several quarters): the alumina market and Chinese supply policy - alumina tightness squeezing margins, and Chinese smelter curtailments (for example when

Yunnan's hydropower falls in a drought) tightening output. Long term (years): lightweighting and electrification demand against the rising cost of clean power and the binding Chinese capacity cap, with decarbonisation reshaping which metal is cheap to make. The cost curve and capacity cap. Because supply growth in China is capped and new smelters elsewhere are slow and expensive to build (and need secure cheap power), the market's longrunning surplus has narrowed, and aluminium is increasingly discussed as a structurally tighter metal, often called "the next strategic metal after copper." The decarbonisation double-edge. Aluminium sits on both sides of the energy transition. It is a beneficiary (lightweight vehicles, solar frames, grid build-out all need it), yet primary smelting is one of the most carbon-intensive industrial processes, accounting for roughly 2% of global emissions when its electricity is included. This drives a growing premium for low-carbon ("green") metal, a shift toward hydro-powered smelting, rapid growth in recycling, and direct exposure to carbon policy such as the EU's carbon border adjustment. Substitution. Aluminium's price is capped by its substitutes: steel in vehicles, copper in cable (aluminium gains share when copper is expensive), and glass and plastic in packaging.

Geopolitics

Aluminium sits across several fault lines, and they tend to be about energy and processing rather than ore scarcity: China's dominance, cap, and power policy. China's control of smelting and alumina refining is its real leverage; its 45 Mt cap and its periodic, power-driven smelter curtailments (Yunnan droughts) directly move global supply. Bauxite resource nationalism. Producing countries increasingly want to capture more of the chain at home. Indonesia banned bauxite exports in 2023 to force domestic refining, and Guinea, the swing supplier of ore to China, carries real political risk (a 2021 coup, and periodic threats to restrict exports) that matters precisely because China depends on it. Russia and Rusal. Russia is a major producer (Rusal). US sanctions on Rusal in 2018 spiked the LME price and disrupted supply chains before being lifted; since 2022, Russian metal has accumulated in LME warehouses, and in 2024 the US and UK moved to bar new Russian metal from the exchanges. Tariffs. US Section 232 tariffs (introduced at 10% and later raised) are built into the Midwest premium, so US trade policy feeds directly into the price American consumers pay. Carbon policy. The EU's carbon border adjustment (CBAM) will charge importers for the embedded carbon in aluminium, advantaging low-carbon metal and reshaping trade flows. Energy and shipping shocks. The Gulf is a major smelting hub (EGA, Alba, Ma'aden, and others), so an energy spike or a disruption to Gulf shipping routes can hit a meaningful slice of world supply, the same channel that affects other energy-intensive exports from the region.

The recurring pattern: because aluminium's constraint is energy and processing (concentrated in China and a few power-rich regions), policy and energy frequently override ore fundamentals in setting the near-term price.

A short history and its cautionary tales

A little history shows why the market is shaped as it is. Once more precious than gold. Before a cheap process existed, aluminium was a luxury metal; Napoleon III is said to have reserved aluminium cutlery for his most honoured guests, and the cap of the Washington Monument was cast in aluminium as a precious metal. The Hall-Héroult smelting process (1886) and the Bayer refining process (late 1880s) together made it cheap and turned it into an industrial commodity, which is why the chain still bears those two names. The LME warehouse-queue saga (early 2010s). After 2008, cheap money and a steep contango fed the stock-financing trade, drawing vast tonnages into LME warehouses (notably Detroit and Vlissingen). Warehouse load-out queues stretched beyond a year, inflating the physical premium consumers paid even while the LME price was low. The episode brought lawsuits and LME rule changes, and it is the defining lesson that a metal's storage and logistics can become a distortion in their own right. The Rusal sanctions shock (2018). US sanctions on Russia's Rusal abruptly removed a major producer from the market on paper; the LME aluminium price jumped sharply and supply chains scrambled, until the sanctions were lifted the following year. It showed how concentrated and policy-sensitive the supply base is. Russian metal after 2022. Following the invasion of Ukraine, traders shunned Russian metal, which then piled up in LME warehouses and raised questions about what the "LME price" represented; the US and UK later barred newly produced Russian metal from the major exchanges. Alumina shocks. The midstream can move on its own: a 2018 curtailment at the giant Alunorte refinery in Brazil and a sharp alumina rally in 2024 both squeezed smelter margins independently of the metal price. The common thread: aluminium can look abundant and cheap, then reveal how much energy, concentration, and the physical plumbing of warehouses and policy actually shape its price.

What to watch: a starter dashboard

The handful of signals that, together, tell you most of what is happening: LME price and the curve (cash versus 3M): the cleanest read on near-term tightness. Regional premiums (Midwest, MJP, European duty-paid and unpaid): real physical demand and the tariff signal. The alumina price (API) and the alumina-to-aluminium ratio: smelter margin pressure from the midstream.

Power and energy prices: especially Chinese power and Yunnan hydro conditions, European energy, and the growing competition from AI data centres for electricity. Chinese output versus the 45 Mt cap, and smelter curtailments: the supply ceiling in action. LME inventory, cancelled warrants, and off-warrant or "shadow" stocks, plus the Russianmetal share: where the metal sits and whether it is trapped or financed. Low-carbon ("green") premium and CBAM developments: the carbon dimension feeding into price and trade. Secondary and scrap availability: the increasingly large recycled share of supply.

How to think about the outlook and the major players

Rather than a price target, the useful habit is asking which variable dominates over which horizon (Section 9), then watching the right actors: China for its supply policy: the cap, power-driven curtailments, and whether it tips from net exporter to net importer of metal. The Gulf, India, and Indonesia for new capacity: the main sources of incremental supply outside China. The alumina market and power markets: the two inputs that most often move smelter margins and the marginal cost of metal. Policy: tariffs (the Midwest premium), CBAM, and the rules on Russian metal. The most informative real-time signals remain the front-end curve (tightness), the regional premiums (location and tariffs), the alumina ratio (midstream margin), and power prices (the swing input). Hold those together and most confusing tape resolves.

Glossary Alumina - aluminium oxide, the white powder refined from bauxite and fed to smelters; a traded commodity in its own right. API - Alumina Price Index, the published benchmark for alumina, usually quoted as a percentage of the metal price. Backwardation - near-dated futures priced above later ones; signals near-term tightness. Bauxite - the reddish ore that is the raw material for aluminium; refined into alumina via the Bayer process. Bayer process - the chemical refining of bauxite into alumina. Billet / ingot / slab / sow - standard cast shapes of primary metal (for extrusion, remelting, and rolling). Capacity cap - China's roughly 45 million tonne self-imposed ceiling on primary smelting capacity; the market's key structural feature. CBAM - the EU's Carbon Border Adjustment Mechanism, which charges importers for embedded carbon, directly affecting aluminium.

Contango - later-dated futures priced above near ones; the "normal" state and the basis of the stock-financing trade. Direct shipping ore - bauxite exported raw, without local refining (common for Guinea). Hall-Héroult process - the electrolytic smelting of alumina into aluminium metal; extremely electricity-intensive. LME - London Metal Exchange; the global benchmark, in dollars per tonne, with physical warehouses. Midwest premium - the US regional delivery premium over the LME price; heavily shaped by import tariffs. MJP - Main Japanese Port premium; the quarterly-negotiated Asian delivery premium. P1020 - the standard primary grade, 99.7% pure aluminium; the exchange-deliverable form. Premium - the extra paid over the exchange price for delivery to a specific place and form. Primary vs secondary - metal made new from ore (primary) versus remelted from scrap (secondary, using about 5% of the energy). Red mud - the caustic waste from bauxite refining; a major disposal and environmental issue. Stock-financing trade - buying metal cheap, selling it forward in a contango, and earning the spread for storing it.

Structural introduction. The mechanics - how bauxite, alumina, smelting, the exchanges, the curve, hedging, and the desks work - are stable; specific figures and the current outlook move and should be checked against live sources before use.