The global zinc mining industry is racing to bring new supply online, but the pipeline may be too little, too late. Glencore — the world's largest listed zinc miner — guided 2026 own-sourced output at just 700,000-740,000 tonnes, down from 969,400 tonnes in 2025, a cut of roughly 250,000 tonnes or 25%. The primary driver is Antamina's terminal grade decline, a multi-year trend that cannot be reversed. (FACT: Glencore, Fastmarkets, LME Week 2025)
Against this backdrop, a slate of projects is aiming for start-up across Africa, Europe, and North America. Fastmarkets' March 2026 base metals outlook identified the following key developments: (FACT: Fastmarkets, March 12, 2026)
Gamsberg expansion (South Africa). Vedanta's Gamsberg mine — already one of the world's largest zinc deposits — is undergoing a major expansion expected to come into operation toward mid-2026. The Gamsberg expansion is the single largest source of new zinc concentrate supply on the horizon, with the potential to add approximately 100,000-150,000 tonnes per year of zinc-in-concentrate at full ramp-up. (FACT: Fastmarkets, March 2026)
Rosh Pinah 2.0 (Namibia). The Rosh Pinah Zinc Corporation, owned by Appian Capital Advisory, is more than 85% complete with its RP2.0 expansion as of February 2026. The project will raise mine throughput from 700,000 to 1.3 million tonnes of ore per year, lifting zinc-equivalent production to roughly 75,000 tonnes per year. Completion is expected in Q3 2026 with ramp-up immediately thereafter. A new paste backfill plant was commissioned in February 2026, ahead of schedule. (FACT: Mining.com, Fastmarkets, February-May 2026)
Tala Hamza (Algeria). Australian miner Terramin began preparatory work at the long-delayed Tala Hamza zinc-lead project in March 2026 after Algeria resolved land access issues, spending $30 million relocating communities. The $471 million project targets significant zinc and lead output, with construction expected to begin later in 2026. No firm production timeline has been confirmed. (FACT: Ecofin Agency, March 25, 2026)
Asmara zinc circuit (Eritrea). A new zinc flotation circuit at the Asmara mine in Eritrea is scheduled for late 2026 to 2027, adding to the country's growing base metals production capacity. (FACT: Fastmarkets, March 2026)
Bunker Hill (USA). The Bunker Hill mine in Idaho — a historic silver-lead-zinc operation — is scheduled for commissioning in early 2026, providing a modest but meaningful addition to North American zinc concentrate supply. (FACT: Fastmarkets, March 2026)
Aljustrel (Portugal). The Aljustrel mine in Portugal has restarted recently, adding European zinc concentrate supply at a time when the continent's smelters are starved for feedstock. (FACT: Fastmarkets, March 2026)
Beyond these six, Orion Minerals agreed a non-binding finance and concentrate offtake deal with Glencore in September 2025 to support a potential restart of the Prieska mine in South Africa in 2026-27. (FACT: Fastmarkets, March 2026)
Even optimistically, the combined new capacity from these projects is unlikely to exceed 300,000-400,000 tonnes per year by 2028. That is roughly enough to offset Glencore's 2026 production cut — but it does nothing to address the structural Western smelter shortage, the Antamina decline beyond 2026, or the continued growth in Chinese smelter demand. Global zinc concentrate production is forecast to grow by only 300,000 tonnes in metal content in 2026, while demand growth is projected to be "more significant," according to SMM. (FACT: SMM, metal.com, December 2025)
The critical risk is timing. The projects ramp up between mid-2026 and 2027, but the supply gap is happening now. LME zinc stocks have already fallen from 230,000 tonnes at the start of 2025 to approximately 96,000-144,000 tonnes by May 2026. Every month of delay in the project pipeline is a month where the deficit deepens and prices remain elevated. (FACT: LME, TradingEconomics)
Do not count on new mine supply to rescue the zinc market in 2026. Even if every project hits its timeline — and mining projects rarely do — the combined additions barely offset Glencore's single-company cut. The zinc concentrate market will remain structurally tight through at least 2027. For procurement planning: assume LME zinc stays above $3,000/t through 2027. Build multi-year contracts now, before the new mine output is committed. The projects that do come online will have their output pre-sold to Chinese smelters; Western buyers need to secure term offtake agreements directly with miners or accept higher spot premiums. Watch Gamsberg and Rosh Pinah ramp-up milestones as your earliest indicators of whether supply relief is on track or delayed.