Indium Ingot
Refined indium cast into ingots, the tradeable form of a metal used mainly in indium tin oxide (ITO) coatings for touchscreens and solar panels.
Covered in 1 MetalsCost.com News Intelligence article, most recently on August 7, 2026.
Overview
Indium ingot is refined indium cast into small bars, the standard tradeable form of a metal that most people have never heard of despite touching it almost every day — indium tin oxide, the transparent conductive coating made largely from indium, is what makes touchscreens on phones, tablets and laptops actually work, allowing a screen to be both see-through and electrically responsive to a fingertip.
Production as a Byproduct Metal
Indium is almost never mined on its own; it occurs in trace concentrations within zinc ores and is recovered as a byproduct during zinc smelting and refining, with smaller amounts also recovered from lead and tin processing. That byproduct status is the single most important thing to understand about indium supply: mining companies don't decide to produce more indium in response to a higher indium price the way they might for a primary metal, because indium output is tied to how much zinc ore gets processed, not to indium economics on its own. That structural link is a major reason indium supply can be slow to respond even to a sharp price increase — smelters would need to process significantly more zinc ore, for reasons that have nothing to do with indium, before meaningfully more indium becomes available.
Applications and Demand Drivers
Beyond touchscreen coatings, indium tin oxide is also used in solar panel manufacturing and in various optoelectronic and semiconductor applications, giving indium demand two structurally growing end markets — consumer electronics and renewable energy — pulling in the same direction at once. Because global indium supply is both small in absolute volume and tightly bound to zinc refining capacity, sudden increases in demand, such as a surge in electronics manufacturing, can move indium prices sharply, in percentage terms, more than would typically be seen in larger, more liquid industrial metals.
How It's Manufactured
Getting from zinc ore to a finished indium ingot takes several separate refining stages. Zinc concentrate is roasted and leached, typically with sulfuric acid, to dissolve the zinc for conventional electrowinning, but indium doesn't follow zinc cleanly into that process — it concentrates instead in the leach residues and slags left behind. Those residues are leached again under different conditions to dissolve the indium, which is then separated from the resulting solution by solvent extraction or cementation with zinc dust, producing a crude indium sponge or metal. That crude material still contains other trace metals and needs further purification, usually a combination of electrolytic refining and vacuum distillation, before it reaches the 99.99% (4N) purity or higher that the market expects, at which point it's cast into small ingots or bars and stamped with the refiner's mark and purity grade.
Byproducts
Indium is never the only valuable metal riding along in zinc-refining residues — cadmium and, in some ore bodies, germanium turn up in the same leach streams and are recovered as separate byproducts by refiners equipped to handle them, which is part of why large integrated zinc-and-byproduct refiners like Korea Zinc are positioned to dominate indium supply rather than smaller, indium-only operations. The leaching and electrowinning stages further upstream also generate iron-bearing residues, commonly precipitated as jarosite, that have to be managed and disposed of as waste rather than sold. Within the indium purification circuit itself, off-specification material that doesn't meet purity requirements is routinely recycled back through electrolytic refining rather than sold at a discount, since a batch that's out of spec for electronics-grade use has essentially no separate market of its own.
