The mining industry is currently facing several operational challenges, including declining ore grades, fewer new deposit discoveries, longer project development timelines, and cautious capital markets. As a result, the sector is increasingly turning to innovation to secure future mineral supply.

One area gaining significant attention is the reprocessing of mine tailings. Historically viewed as a liability, these accumulated materials are now being reassessed as valuable pre-extracted assets.

The sheer scale of global accumulated mine tailings is remarkable, as highlighted in the infographic:

  • 217 km³ — The total volume, enough to form a cube approximately 6 km × 6 km × 6 km.
  • ~282 billion tonnes — Stored across an estimated 8,500 facilities.
  • More than $2.5 trillion — In contained metal value*.
  • 70,500 gigalitres — Approximate water content held within these facilities.
  • 12.3 km³ per year — The estimated annual increase in global tailings volume.

These accumulated materials contain significant quantities of valuable metals and minerals left behind by older, less efficient extraction methods. They include major commodities such as Copper, Nickel, Iron Ore, Zinc, Lead, Gold, and PGMs (Platinum Group Metals).

Today, advances in processing are making it possible to economically extract these metals, turning legacy mine waste into a new source of value while simultaneously rehabilitating the land. Key methods being adopted by the industry include:

  • AI Analytics to pinpoint valuable assets.
  • Advanced Separation to maximize recovery.
  • Biotech (biological methods) to recover minerals.
  • Dry Processing to recover and reuse water.

Several mining companies are already implementing these strategies as part of a "circular mining" shift:

  • Hindustan Zinc is scaling up to reprocess 10 million tonnes of tailings annually.
  • Vale aims for 10% of its iron ore output to come from tailings by 2030 and is moving its Carajás complex to dry processing.
  • Glencore is using its proprietary processes to achieve over 99% copper recovery.
  • Allonnia is using biotech to lift nickel grades from waste.

This industry trend is aligned with government action. In the United States, the Interior Department has designated the recovery of critical minerals from waste streams as a national priority.

The US Geological Survey's 2025 List of Critical Minerals identifies 60 commodities essential to security and the economy. This includes key targets for reprocessing such as Rhodium, Gallium, Germanium, Tungsten, and Rare Earth Elements (REEs). By targeting these materials in waste streams, the industry is positioning reprocessing not just as an environmental solution, but as a cornerstone of national energy and supply chain security.