Endeavour Silver Reports Temporary Reduced Capacity at its Guanacevi Mine

Endeavour Silver Corp. (EDR) identified a mechanical issue with the primary ball mill at its Guanaceví mine in Durango, Mexico, and took the unit offline on Sept 21, 2026. The company plans to repair the equipment by replacing the mill head and trunnion, both of which are already in inventory on site. Third-party service providers are being coordinated to expedite the work.

The repair is expected to take approximately three weeks. During this period, the regrind circuit will be reconfigured to operate at a reduced capacity of 600 tonnes per day (tpd), down from the ordinary course capacity of approximately 1,100 tpd. This represents a throughput reduction of roughly 45% at the asset. Mining operations will continue uninterrupted, allowing ore to be stockpiled rather than lost.

Endeavour described the financial impact as minimal because the replacement components are already in inventory. However, the company’s forward-looking disclaimer explicitly flags the expected impact of this reduced capacity on Q3 production at Guanaceví as a risk, indicating a production hit of unquantified size for the quarter. No production, cost, revenue, or earnings figures are reported in this release, which serves as a single-mine equipment update rather than an earnings release.

Endeavour Silver Corp. (EDR) issued a non-earnings operational update regarding a temporary outage at its Guanaceví mine. The company did not provide specific production figures in the release, so estimates rely on Q2 2026 operating data as a baseline. During that period, Guanaceví processed approximately 1,104 tons per day (tpd) at grades of roughly 235 grams per ton (g/t) silver and 0.94 g/t gold. Silver recovery stood at 92.4%, while gold recovery was 92.9%.

The outage lasted three weeks, beginning September 21. At a processing rate of 1,100 tpd, the facility would have handled approximately 23,100 tons over that period. At a reduced rate of 600 tpd, it processed roughly 12,600 tons, creating a throughput shortfall of approximately 10,500 tons. This volume equates to roughly 73,000 ounces of silver and 300 ounces of gold before recovery losses, or approximately 98,000 ounces of silver-equivalent (AgEq) based on the company’s 85:1 ratio.

Scaled against Q2 2026 consolidated output of 1,943,955 ounces of silver and 3.4 million ounces of AgEq, the shortfall represents roughly 2–4% of a quarter’s production. Against full-year 2026 guidance of 14.6–15.6 million ounces of AgEq, the impact is under 1%. Because the three-week outage starting September 21 straddles the quarter-end, only about 9–10 days fall within the third quarter (September 21–30), with the remainder landing in the fourth quarter. Consequently, the hit to Q3 silver production is likely only 1.5–2%, with the balance pushing into Q4.

Guanaceví is Endeavour Silver’s highest-cost, weakest-margin mine, reporting Q2 2026 cash costs of US$40.17 per ounce and all-in sustaining costs (AISC) of US$52.20 per ounce. Lost throughput at this site carries a smaller cash-margin cost than an equivalent loss at the Terronera mine. The company stated that repair components are already on site, making direct repair costs immaterial.

Mining operations at Guanaceví continue, allowing ore to be stockpiled. Some of the deferred throughput may be recovered later if the plant catches up, though the company has not promised this recovery. The event is assessed as a modest, temporary, single-asset negative that does not alter the broader production outlook.

Endeavour Silver Corp. (EDR) is a mid-tier silver producer operating three mines: Terronera in Jalisco, Mexico; Guanaceví in Durango, Mexico; and Kolpa/Huachocolpa Uno in Huancavelica, Peru. The company also maintains a development and exploration pipeline that includes Pitarrilla in Durango, which is currently undergoing a feasibility study, as well as projects at Parral in Chihuahua, Bruner in Nevada, and Aida.

The company sold the Bolañitos mine to Guanajuato Silver, with the transaction closing on January 15, 2026. The deal structure included US$30 million in cash, US$10 million in shares, and up to US$10 million in contingent consideration. Consequently, production from Bolañitos is no longer included in the company’s operations.

Endeavour Silver produces silver, gold, lead, zinc, and copper. The company’s AgEq methodology converts silver to gold equivalents using a ratio of 90 silver ounces to 1 gold ounce. Management has described its strategic direction as the path "to becoming a leading senior silver producer."