The Tres Oros Mine is a 445-acre property (~180 hectares) permitted for both mining exploration and extraction, which supports near-term production. Tres Oros provides a source of ore as part of Exter's vertically-integrated model, further reinforced by long-term resource growth with underground mine development underway. The property has ​both resource expansion and discovery potential,​ with an independent, third-party verified 43-101 inferred resource report showing 300,000 tons of high-grade ore. 

 

Tres Oros is located within a strong jurisdiction with infrastructure, 47 km SE of Mazatlán. The Tres Oros claim is centred among 23 claims, a stable modern electric grid, accessible via $10 billion new superhighway, only 4 km from Exter's processing facility, Tadeo Mill.

 

Tres Oros is known as a hybrid epithermal project: Evidence of both low and high sulfidation (epithermal) features, discovered presence of a high grade copper, gold, silver and lead zone. 

 

Per the Company's news release (December 11, 2025) regarding the binding letter of intent with Analog Gold Inc. to acquire certain assets, Exter is pleased to update that the preparation of a technical report for the Tres Oros Mine pursuant to National Instrument 43-101 - Standards of Disclosure for Mineral Projects is progressing well, and the parties continue to advance the steps necessary to complete the Transaction.

 

The development of the Tres Oros Mine has advanced as per plan and the mine has entered production, where nearby Tadeo Mill commenced processing Tres Oros ore in April 2026. The first revenue from Tres Oros Mine concentrate is expected in June 2026.