Indium and Zinc
Most indium is recovered from residues of zinc smelting, so its supply depends on how much zinc is smelted and where, not on indium's own price; China refined about 70% of it in 2025.
Indium (commodity) and Zinc (commodity): 4 relationships.
How they are linked
1. By-product of zinc smelting
Joint production · Strong · Zinc ore to indium
Indium sits in trace amounts in the zinc sulphide mineral sphalerite and gathers in the dusts and residues of zinc smelters, where it is leached and refined.
- about 1,100 t world refined indium output, 2025
- about 13 Mt world zinc mine output, 2025
Indium output is roughly one ten-thousandth of zinc output by weight. Not every smelter recovers it, so a significant share of the indium in zinc ores is lost.
2. Inelastic supply
Shared risk · Asymmetric · Indium supply follows zinc smelters
Indium is a trace by-product next to zinc in the same concentrate, so smelters decide output on zinc economics; a higher indium price can lift recovery at existing plants but cannot add ore.
- $390 per kg average US warehouse indium price, 2025, up 11%
USGS notes that changes in zinc mine output may not match changes in indium output, since recovery depends on which smelters receive the concentrate and whether they have indium circuits. Supply therefore reacts slowly to demand from displays and chips.
3. China's smelting dominance
Geography and ownership · Strong · China leads zinc mining and indium refining
China mines the most zinc and also refines most of the world's indium and can steer supply through export rules.
- 70% China's share of world refined indium, 2025
- 4.1 Mt China zinc mine output, 2025, about 32% of world
- 72% fall in China's unwrought indium exports, 2025, after new export restrictions
China placed indium under new export restrictions, and its exports of unwrought indium fell by 72% year on year in 2025, tightening supply for buyers elsewhere.
4. ITO for displays
Transition · Medium · Displays and touchscreens pull on zinc by-product
Indium tin oxide is the transparent conductive coating in flat panel displays and touchscreens, and it takes most of the world's indium.
Recycling of ITO scrap in Japan and South Korea adds supply that does not depend on zinc. Antimony tin oxide coatings have been developed as an alternative to ITO in LCDs, giving buyers some room if indium becomes very expensive.
For investors
Key learnings
- Indium supply is set by zinc smelting decisions, so zinc smelter closures or concentrate shortages are indium supply risks.
- With about 70% of refined indium from China and Chinese export restrictions in force since 2025, buyers outside China face tighter supply, as the 72% fall in China's unwrought exports showed.
- ITO dominates use, so display panel output is the main demand signal, partly offset by scrap recycling.
What to track
- Indium price (US warehouse and China): Spread shows the effect of Chinese export controls (Monthly · USGS and Argus or Fastmarkets)
- Zinc smelter output and closures outside China: Changes the base for non-Chinese indium recovery (Monthly · ILZSG)
For policymakers
Key learnings
- Indium security depends on having zinc smelters with indium recovery circuits, so smelting policy is also minor metals policy.
- Export controls on indium show how a by-product can become a lever when refining is concentrated in one country.
- Indium is not mined for its own sake, so recovering more from zinc residues and ITO scrap is the practical way to add supply.
What to track
- China indium export volumes: Effect of export controls on world supply (Monthly · China customs data)
- Indium recovery at domestic zinc smelters: Whether residues are being processed rather than stockpiled (Yearly · company reports and ministries of mines)
Sources
- Mineral Commodity Summaries 2026: Indium, USGS (2026)
- Minerals Yearbook 2023: Indium, USGS (2023)
- Mineral Commodity Summaries 2026: Zinc, USGS (2026)