Alma smelter: an aluminum operation in Canada
Alma smelter is an aluminum smelter producing aluminum in Alma, Quebec, Canada, operated by Rio Tinto. The sources report 485 '000 tonnes (kt) of primary aluminum, 100% basis ('Total' column) for CY2025; the basis is 100% of the smelter, as printed by Rio Tinto. Measured as primary aluminum, whole-operation output for CY2025 is 485,000 tonnes: about 0.7% of world aluminum output in 2025 and about 15% of Canada's; it is one of 28 operations on this site whose output can be stated in primary aluminum.
Who owns and operates it?
| Owner | Interest | As of |
|---|---|---|
| Rio Tinto | 100% | 31 December 2025 |
How much does it produce?
| Period | Output | Basis | Where in the source |
|---|---|---|---|
| CY2025 | 485 '000 tonnes (kt) of primary aluminum, 100% basis ('Total' column) | 100% of the smelter, as printed by Rio Tinto | printed p.276 (PDF p.278), table 'Metals and minerals production', block 'ALUMINIUM (primary) (thousand tonnes)', row 'Alma (Canada)', column '2025 Production, Total' · Rio Tinto |
| CY2024 | 483 '000 tonnes (kt) of primary aluminum, 100% basis ('Total' column) | 100% of the smelter, as printed by Rio Tinto | printed p.276 (PDF p.278), table 'Metals and minerals production', block 'ALUMINIUM (primary) (thousand tonnes)', row 'Alma (Canada)', column '2024 Production, Total' · Rio Tinto |
Between CY2024 and CY2025 the reported figure rose by 0.4%, in the same unit and on the same basis.
How the primary-aluminum figure is worked out. Rio Tinto's 2025 annual report prints 485 thousand tonnes in the 'Total' column (whole smelter) for 2025. Rio Tinto reports in thousand tonnes, so the figure converts to 485,000 tonnes. World smelter production of primary aluminum in 2025 was 74,000,000 tonnes (USGS Mineral Commodity Summaries 2026); Canada produced 3,300,000 tonnes.
Status: operating, as of 30 September 2026.
- Rio Tinto's table covers primary aluminum only; recycled production is reported on a separate line and is not included.
How does it compare?
Other aluminum operations on this site: Alouette smelter, Bécancour smelter, Boyne Island smelter, Tomago smelter, Kitimat smelter, Tiwai Point smelter, Sohar smelter, Laterrière smelter, Grande-Baie smelter, ISAL smelter, Bell Bay smelter, Arvida smelter. In Canada: Alouette smelter, Bécancour smelter, Kitimat smelter, Laterrière smelter, Grande-Baie smelter, Arvida smelter, Arvida AP60 smelter. See where aluminum comes from for the country totals, the country page for Canada, and Rio Tinto for its other operations here.
Sources
- Rio Tinto: Annual Report 2025 (annual report (filed with the SEC on Form 6-K, 2026-02-19), CY2025, with 2024 and 2023 comparatives). Opened 4 November 2026; used: printed p.276 (PDF p.278), 'Metals and minerals production'; PDF p.160.
- Rio Tinto: Rio Tinto releases third quarter 2026 production results (third quarter operations review) (quarterly operations review (SEC Form 6-K exhibit, 2026-10-14), Q3 2026 and nine months to 30 September 2026). Opened 4 November 2026; used: printed pp.9, 28.
- U.S. Geological Survey: Mineral Commodity Summaries 2026: Aluminum (government statistical summary, 2025 (world and country smelter production)). Opened 3 November 2026; used: world smelter production and capacity table.
Method and limits
- Reported, not estimated. Output is the figure the operator or owner published, in the unit it used. This site does not estimate output where none is published.
- Shares. A share divides output in primary aluminum by the USGS world or country total for 2025. Where the operator's year is a fiscal year or the unit is a concentrate or a carbonate equivalent, the share is approximate or not given.
- What is compared. The figure is tonnes of primary aluminum metal produced by the whole smelter, compared with USGS smelter production of primary aluminum. Remelted and recycled metal is not primary production.
- Whole operation or owner's share. The basis column says which. A joint venture's output is never counted twice.
- Partial list. Only operations with a published figure are listed, so the rank is among those on this site, not among every aluminum mine. Shares of a country's output mix periods and bases, so treat them as indicative.
- Made with AI assistance, checked against sources. The facts were gathered from the documents above by AI-assisted research and re-checked against those documents by a second, independent pass; the page text is generated from the data. No professional review took place. How the site is made. To report an error, contact us; fixes are logged on the corrections page.