Sierra Madre Gold and Silver Ltd. (TSXV: SM) (OTCQX: SMDRF) has announced that its Guitarra silver-gold processing plant in Estado de Mexico, Mexico, has reached throughput of up to 720 tonnes per day following Phase 1 expansion modifications — a more than 40% increase over the previous nameplate capacity of 500 tpd. The company also confirmed the installation of a new 11x12 ball mill, with commissioning expected in November 2026. The operational update signals accelerating progress toward Phase 2 production targets, which investors may be watching closely.

Key Points

  • Sierra Madre Gold and Silver Ltd. (TSXV: SM) (OTCQX: SMDRF) operates the Guitarra mine complex in Estado de Mexico, Mexico.
  • Processing plant throughput has reached up to 720 tpd, exceeding the previous 500 tpd nameplate capacity by more than 40%.
  • The new 11x12 ball mill has been installed and is expected to help achieve Phase 2 targets of 1,200–1,500 tpd, more than eight months ahead of schedule.
  • Investors may watch for commissioning of the new ball mill in November 2026 and initial production from higher-grade Guitarra blocks by end of October 2026.

Guitarra Processing Plant Surpasses 500 tpd Nameplate Capacity

Following Phase 1 modifications to existing crushing and milling circuits, Sierra Madre's Guitarra processing plant has achieved steady throughput of up to 720 tpd. The company states this represents more than a 40% improvement versus the prior nameplate capacity. Foundation construction for the new 11x12 ball mill required 400 cubic metres of cement and 16 tonnes of steel rebar. Installation of the drive motor, cyclones, and instrumentation is under way, with commissioning targeted for November 2026. Once operational, the combined milling capacity is expected to meet Phase 2 targets of 1,200–1,500 tpd — reportedly more than eight months ahead of the original schedule.

Underground Development Advances Across Guitarra, Nazareno, and Coloso

The company reports approximately 2.6 kilometres of development drives completed across all three mines within the La Guitarra complex since June 2026, with over 800 metres of access and production drives completed since July 2026. At the Guitarra mine alone, over 1.5 kilometres of development has been completed since June 2026. The lower Central mine area now contributes a meaningful portion of mill feed, and development work for the Los Angeles bulk tonnage deposit has commenced. The current mine plan calls for initial production from higher-grade blocks by end of October 2026, according to the release.

Dry Stack Tailings Expansion and Permitted Capacity

Ground works for the fully permitted Phase 4 dry stack tailings facility expansion have begun, the company announced. Vegetation clearing is scheduled for October, with the chosen earthworks contractor expected to mobilise in November 2026. The first construction phase is designed for a capacity of 877,000 tonnes, with total permitted area capacity stated at over 5,000,000 tonnes. Sierra Madre also disclosed that it is examining the possible future development of the East District's Santa Ana deposit, with an initial mine design completed and portal construction being contemplated for 2027.