Material Insights · Understanding the Material World

Aluminium: Characteristics

Light, conductive and rust-proof: the alloy toolkit

What this tab covers The supply and physical characteristics of the commodity. Supply: current production, inventories and stocks, capacity utilisation, geographic and producer concentration, how fast supply responds to price, the project pipeline and capital spending, and logistics and export flows. Material: the physical and chemical properties that set its grade, price and end uses (for example purity and conductivity for metals, API gravity, sulfur and energy content for fuels, moisture, protein and fibre quality for crops).

Supply volume characteristics

CharacteristicFigureWhat it meansSource
Current production volumeabout 74 Mt primary aluminium (2025e); 150 Mt alumina; 440 Mt bauxiteChina produced 45 Mt, about 60% of the world. India was second with 4.2 Mt. The IAI counted 73.8 Mt of primary output in 2025.USGS MCS 2026; IAI
Inventory and stock levelsUS industry stocks 1.8 Mt at end-2025, about 4 months of US use; LME US warehouses only 8 ktWorld stocks are spread across producers, traders and LME, SHFE and off-warrant warehouses, and are not fully published. At about 74 Mt of primary output a year, 1 Mt of stock equals about 5 days of world primary supply (derived).USGS MCS 2026; derived
Capacity utilisationabout 93% of world smelter capacity (74.0 Mt output against 79.7 Mt capacity, 2025e)China ran at about 100% of its 45 Mt capacity, which matches its policy cap of about 45 Mt (indicative). India ran at about 100% of 4.2 Mt. The US used only half of its 1.31 Mt, with two smelters idle.USGS MCS 2026; China cap indicative
Geographic and producer concentrationChina 60.0%, top-3 (China, India, Russia) 71.4%, HHI 3,719 (smelting); bauxite: Guinea 34.2%, HHI 2,106; top-5 companies about 32%Chalco (8.08 Mt), China Hongqiao (5.82 Mt), Rusal (3.99 Mt, 2024), Rio Tinto (about 3.3 Mt) and EGA (2.84 Mt) make about 24 Mt (derived). Guinea and Australia mine 58% of bauxite.World Mining Data 2026; company reports via this tile's lessons
Supply elasticitymedium: idle smelters restart in 6-12 months; new smelters take about 3-4 yearsSupply depends on power. Smelters close when power is costly, as in Europe in 2022, and restart when it eases: San Ciprian in Spain restarted in 2025. China's cap stops its supply from responding to price.USGS MCS 2026; this tile's lessons (indicative)
Project pipeline and CapExnew smelter capacity mainly in Indonesia, India and the Gulf (indicative)Named projects: a 500 kt/yr smelter in North Kalimantan, Indonesia; a restart of more than 50 kt/yr at a 229 kt/yr South Carolina smelter by mid-2026; new potlines in Guangxi, Guizhou, Qinghai, Sichuan and Yunnan; a 1 Mt/yr alumina refinery at Mempawah, Indonesia. In India, Vedanta is expanding BALCO and Hindalco its Aditya smelter (indicative).USGS MCS 2026; company announcements (indicative)
Logistics and export flowsunwrought aluminium exports worth $56 billion in 2024; China took 87% of bauxite imports by valueGuinea ships bauxite from Boke and Kamsar to China, and Australia from Weipa and Gove. The Gulf and Indian smelters export ingot and billet by sea. Bauxite supply is exposed to Guinean policy, as in 2025 when licences were revoked.UN Comtrade 2024; USGS MCS 2026

Material characteristics Metal / hard commodity

Aluminium is light (a third of the density of steel), conducts electricity well for its weight, resists corrosion through a thin oxide film and is easy to cast, roll and extrude. Purity sets exchange deliverability; alloying with magnesium, silicon, zinc or copper sets strength. Bauxite is valued on alumina content and reactive silica, which wastes caustic soda.

PropertyValue / specificationWhy it mattersSource
Purity / gradeLME P1020A: at least 99.7% Al, at most 0.10% Si and 0.20% FeSets deliverability on the LME and the base for alloy makingLME
Density2.70 g/cm3Lightweighting in vehicles, aircraft and packagingASM Handbook
Electrical conductivityabout 61-62% IACS for EC grade (1350)Per kg it conducts about twice as well as copper, so overhead lines use itASTM B230 (indicative)
Strengthpure aluminium about 90 MPa; 6061-T6 about 310 MPa; 7075-T6 about 570 MPa tensileAlloys reach steel-like strength at a third of the weightAluminum Association (indicative)
Thermal conductivityabout 237 W/m K for pure metalRadiators, heat sinks and cookwareASM Handbook (indicative)
Bauxite gradeabout 40-60% Al2O3; low reactive silica, typically under 5-8%Sets alumina yield and caustic soda use in the Bayer processIndustry practice (indicative)