Summary

Mine Type	Open Pit
Study Completed	Feasibility
Status	Inactive / Suspended
Commodities	Lithium Potassium
Mining Method	Truck & Shovel / Loader
Mine Life	...
Snapshot	The Sonora Project is a lithium mine and processing facility, based on concessions granted prior to Mexico’s 2022–2023 Mining Law reforms that nationalized lithium and restricted private participation. The Company asserts that its concessions are legally protected and has engaged with the government seeking collaboration, though no agreement has been reached. In January 2024, the Company’s Mexican subsidiaries filed legal claims challenging the cancellation of nine concessions. Legal counsel sees merit in the case, but the outcome is uncertain. Separately, in May 2024, Ganfeng and its subsidiaries initiated arbitration proceedings at ICSID over Mexico’s actions. The case has been registered, but no hearings have occurred, and the outcome and potential compensation remain unknown.

Deposit type

• Hydrothermal
• Sedimentary

Summary:

The Sonora deposit is believed to have formed by hydrothermal alteration as a result of alkaline volcanism effecting layers of volcaniclastic sedimentary rocks deposited in a basin environment. The origin and timing of the mineralised content remains unclear with regard to source and whether the alteration was essentially syn-genetic with deposition of the sedimentary rocks or whether the alteration is a post depositional event. Additional work is required to clarify the origin of these deposits.

Mineralisation on the concessions consists of a series of lithium-bearing clays that occur within two bedded sequences, the Upper and the Lower Clay units, which are separated by an ignimbrite sheet.

Bacanora understands there to be a number of lithium-bearing clay minerals, with polylithionite being the only one currently positively identified. The clay units are believed to have formed from supergene or diagenetic alteration of volcanic ash. The clay layers also contain relict quartz and feldspar crystal shards, lithic fragments and silica bands, and traces of other minerals. The layers are locally interbedded with reddish terrigenous beds composed of sand and silt-sized material.

Initial interpretation has indicated a high grade lithium core in the area covered by the La Ventana, El Sauz and Fleur concessions where the lithium grades are generally above 3,000 ppm Li. This high grade zone extends from the middle of La Ventana southward across Fleur and approximately a third of the distance south into El Sauz. The best grades of lithium are associated with elevated levels of calcium, caesium, magnesium, potassium, rubidium and strontium; however, the correlation (especially for magnesium) is not one-toone.

On La Ventana, the best grades of lithium are co- incident with elevated levels of potassium and caesium and are found in the southern part of the deposit. Magnesium appears to be irregularly distributed and does not follow lithium or the other alkalis. Mineralised intervals within the clay units vary for the Upper Clay Unit from 25% to 80% of the overall thickness and from 40% to 100% for the Lower Clay Unit, depending on the cutoff used.

Further mineralogical studies are recommended to determine what minerals host the various alkalis in the clay units. Results of such studies could have an impact on beneficiation of these minerals and recovery of the alkalis.

Mining Methods

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Comminution

Crushers and Mills

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Processing

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Water usage

Commodity Production

Operational metrics

Personnel

Job Title	Name	Profile	Ref. Date
.......................	.......................		Jun 5, 2025