Sangaredi (Compagnie des Bauxites de Guinee): a bauxite operation in Guinea

Sangaredi (Compagnie des Bauxites de Guinee) is an open-pit mine producing bauxite in Sangaredi, Boke region, Guinea, operated by CBG. The sources report 17,032 thousand tonnes ('000 tonnes), marketable quantities of ore plus concentrates for CY2025; the basis is 100% of the operation, reported by Rio Tinto as a 22.95% shareholder. Measured as bauxite, whole-operation output for CY2025 is 17,032,000 tonnes: about 3.9% of world bauxite output in 2025 and about 11% of Guinea's; it is one of 9 operations on this site whose output can be stated in bauxite.

Who owns and operates it?

Owners of Sangaredi (Compagnie des Bauxites de Guinee)
Owner	Interest	As of
Rio Tinto Held through Halco (Mining) Inc., in which Rio Tinto holds 45%. Halco holds 51% of CBG. Rio Tinto benefits from 45.0% of CBG's production according to the production-table note.	22.95%	31 December 2025
Alcoa Held through Halco (Mining) Inc., in which Alcoa World Alumina LLC holds 45%; Boke Investment Company, owned 100% by Halco, holds 51% of CBG.	22.95%	31 December 2025
Government of Guinea Direct shareholding in CBG.	49%	31 December 2025
Dadco Investments Limited Listed in the Rio Tinto ownership box.	5.1%	31 December 2025

Interests are as stated in the sources below on the date shown. Ownership changes with deals, so a stake may have changed since the date shown.

How much does it produce?

Reported output of Sangaredi (Compagnie des Bauxites de Guinee)
Period	Output	Basis	Where in the source
CY2025	17,032 thousand tonnes ('000 tonnes), marketable quantities of ore plus concentrates Rio Tinto's share column prints 7,665 thousand tonnes, which is 45% of the Total, as note 5 explains. The table does not say whether tonnes are dry or wet. Alcoa prints 3.7 million dry metric tons as its 22.95% share for 2025.	100% of the operation, reported by Rio Tinto as a 22.95% shareholder	PDF p.278 (printed p.276), section BAUXITE ('000 tonnes), row Sangaredi (Guinea), 2025 Production 'Total' column; note 5 on PDF p.279 (printed p.277) · Rio Tinto
CY2024	14,043 thousand tonnes ('000 tonnes), marketable quantities of ore plus concentrates	100% of the operation, reported by Rio Tinto as a 22.95% shareholder	PDF p.278 (printed p.276), same row, 2024 Production 'Total' column · Rio Tinto

Between CY2024 and CY2025 the reported figure rose by 21.3%, in the same unit and on the same basis.

How the bauxite figure is worked out. The source reports 17,032 thousand tonnes for Sangaredi in 2025 in the Total column of Rio Tinto's production table. Rio Tinto is a 22.95% shareholder and not the operator. The table gives marketable quantities of ore plus concentrates and does not say whether tonnes are dry or wet. Converted from thousand tonnes to tonnes. World bauxite mine production in 2025 was 440,000,000 tonnes (USGS Mineral Commodity Summaries 2026); Guinea produced 150,000,000 tonnes.

Status: operating, as of 31 December 2025.

The figure comes from Rio Tinto, a minority shareholder. The Ministry of Mines and Geology of Guinea prints CBG production of 5,579,804 t in the first quarter, 4,708,678 t in the second quarter and 4,090,191 t in the third quarter of 2025; the bulletins do not state a basis and no full-year 2025 ministry figure is used.
Sources differ. Alcoa's 10-K prints 3.7 million dry metric tons as its 22.95% attributable production for 2025, which is about 16.1 million tonnes when divided by 0.2295 (arithmetic only; Alcoa does not print a whole-mine figure). Rio Tinto prints 17,032 thousand tonnes. The reasons for the difference are not stated in either document. For 2023 the ministry's annual bulletin prints 16,442,083 t for CBG, against 14,278 thousand tonnes in Rio Tinto's 2023 column.
Alcoa's 10-K says it holds 45% of Halco (Mining) Inc., which owns 51% of CBG through Boke Investment Company, and that the amount of bauxite Alcoa buys from CBG differs from its proportional equity in the mine.
Alumina refineries and aluminum smelters are separate from this bauxite mine entry.

How does it compare?

Other bauxite operations on this site: Weipa (including Amrun), Gove, Porto Trombetas (Mineracao Rio do Norte), Societe Miniere de Boke (SMB), Boffa (Chalco Guinea), Pingguo, Shanxi New Materials mines (merged line), Darling Range (Huntly and Willowdale), Juruti, Pocos de Caldas, Paragominas, Panchpatmali bauxite mines. In Guinea: Societe Miniere de Boke (SMB), Boffa (Chalco Guinea). See where bauxite comes from for the country totals, the country page for Guinea, and CBG for its other operations here.

Sources

Rio Tinto: Rio Tinto Annual Report 2025 (annual report (filed with the U.S. SEC as an exhibit to Form 6-K), FY2025 (calendar), with 2024 and 2023 comparatives). Opened 4 November 2026; used: PDF p.29 (printed p.27), PDF p.160, PDF pp.278-279 (printed pp.276-277, Metals and minerals production), PDF pp.306-307 (printed pp.304-305, Group mines).
Alcoa Corporation: Form 10-K for the year ended 31 December 2025 (annual report (SEC 10-K), FY2025 (calendar), with 2024 and 2023 comparatives). Opened 4 November 2026; used: cover page; printed pp.3, 10, 32-35, 46 (Item 1 Alumina segment; Item 2 Properties, bauxite production, interests and mine types tables).
U.S. Geological Survey: Mineral Commodity Summaries 2026: Bauxite and Alumina (government statistical summary, 2025 (world and country bauxite mine production)). Opened 3 November 2026; used: world mine production and reserves 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 bauxite 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. Operators print tonnes of bauxite on a dry or wet basis, or do not say which. USGS bauxite mine production is in dry tonnes, so where the basis differs or is not stated the share is indicative.
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 bauxite mine. Shares of a country's output mix periods and bases, so treat them as indicative.
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