Indium

1. China's roughly 70% refinery share, and the specific smelters behind it

USGS MCS 2026 puts China's 2025 estimated refinery production at 760 tonnes of a 1,100-tonne world total — approximately 69–70% of global supply — against a domestic refinery capacity of 1,100 tonnes, meaning China alone could in theory supply the entire current world market (USGS MCS 2026). Production is spread across a handful of zinc/lead/tin smelters rather than one dominant national champion. Yunnan Tin Co. Ltd.'s Dulong mining area holds indium resource reserves the company describes as "ranking first globally," with 4,821 tonnes of retained indium metal reserves as of 31 December 2024 and 101.62 tonnes of indium produced in the first three quarters of 2025 alone (FuTu News, 26 Feb 2026). Yunnan Chihong Zinc & Germanium operates its Hulunbuir Chihong Mining subsidiary as a crude (99.5%) indium producer and separately runs downstream compound-semiconductor lines, though as of December 2025 the company stated it does not currently produce indium phosphide at Chihong Zinc & Germanium itself — that capability sits with its affiliate Yunnan Germanium Industry, which made 64,400 InP wafers (2–4 inch) in 2024 (USGS 2021 Minerals Yearbook, indium; FuTu News, Zhuzhou Smelter investor Q&A, 22 Jun 2026; Metal.com, Yunnan Germanium Industry 2024 annual report summary). Zhuzhou Smelter Group (Hunan) runs a designed indium production line of approximately 60 tonnes/year as a byproduct of its 680,000 t/yr zinc-alloy and 100,000 t/yr lead operations, alongside cadmium, bismuth, tellurium and gold recovery, and told investors in June 2026 it has no plans to expand indium capacity and does not make 7N (99.99999%) ultra-high-purity indium (FuTu News, 22 Jun 2026; Metal.com, Zhuzhou Smelter Group product profile, 23 May 2025). Nanjing's indium/germanium processing base traces to the former Nanjing "718" factory, now China Germanium Co. (CNGE), which specializes in germanium, indium and gallium separation, refining and recycling, alongside smaller specialist compound-semiconductor makers such as Nanjing JinMei Gallium, which produces high-purity indium phosphide (China Germanium Co. (CNGE) company profile; JinMei Gallium company profile). China's smaller producers have historically been vulnerable to environmental-compliance shutdowns: Nanjing Germanium Factory, Zhuzhou Touch Smelting, Yunnan Copper Zinc and several others collectively producing 50–60 t/yr of indium ceased output in 2018 amid tightened environmental regulation, illustrating how policy-driven consolidation, not resource scarcity, periodically tightens Chinese supply (USGS 2018 Minerals Yearbook, indium).

2. World refinery production and capacity by country, 2024–2025

Source: USGS MCS 2026. World refinery production was essentially flat 2024→2025, but the capacity overhang (1,700t vs. ~1,100t actual output) shows more than a third of global nameplate indium capacity sits idle — a buffer that can theoretically absorb demand growth, but only if zinc throughput and indium-recovery economics justify running it.

3. Korea's rising position and its own deepening China dependency

South Korea is the leading non-Chinese refiner at 180 tonnes/year (2025e), all of it from Korea Zinc's Onsan smelter, which the company describes as the country's sole producer of indium, antimony and bismuth (Korea Zinc corporate disclosure, cited via Wikipedia, 2025). Onsan recovers an additional 100 tonnes/year of indium during its integrated zinc-and-lead smelting process, on top of leading production of antimony, bismuth and tellurium from the same feedstock stream (Chosun Biz, 8 Mar 2026). Yet South Korea's own upstream exposure to China has widened even as it supplies the West: China's share of South Korean indium imports rose from 44.1% in 2015 to 94.2% in 2025, with Korea importing $86.5 million of indium in 2025 — meaning Korea Zinc's finished-metal exports to the US, Japan and Taiwan increasingly rest on Chinese-origin intermediate feedstock even as Seoul markets itself as the Western alternative to Chinese refining (The Diplomat, 15 Jun 2026).

Why it matters: because indium output is capped by zinc-smelting throughput rather than dedicated indium mining, no amount of price incentive can quickly summon new primary supply. Every non-Chinese expansion plan — Korea Zinc's Tennessee smelter, Teck's Trail byproduct stream, Nyrstar's Auby and Balen assets — is bolted onto existing or planned zinc-processing infrastructure, not a standalone indium mine.

China Export Controls: Indium Joins the 2025 Control List

On 4 February 2025, MOFCOM and the General Administration of Customs jointly issued Announcement No. 10 of 2025, updating China's Dual-Use Item Export Control List (Announcement No. 51 of 2024) to add export-licensing requirements on tungsten, tellurium, bismuth, molybdenum and indium. The measure took effect the same day it was published.

Critically, unwrought indium metal itself was not placed under control. The controlled items are narrower and higher-value: indium phosphide (InP), and the metal-organic precursors trimethylindium (TMI) and triethylindium (TEI), plus the technology and data used to produce them (MOFCOM text via Shanghai Metals Market). Fastmarkets reported the global indium phosphide market is highly concentrated — Japan's Sumitomo Electric and US-based AXT together control nearly 80% of supply — meaning the license regime targets the compound-semiconductor choke point rather than the base metal trade.

Refined indium metal was separately caught by a broader U.S. tariff action: in September 2024 the USTR finalized Section 301 tariff modifications placing a 25% ad valorem tariff on unwrought indium and indium powders (HTS 8112.92.30) imported from China, effective 27 September 2024 (USGS MCS 2025).

Why it matters: China refines roughly 70% of world indium, recovered almost entirely as a byproduct of zinc smelting (USGS MCS 2026). The United States is 100% import-reliant for indium and produces none domestically. Indium phosphide underpins 5G/AI optical interconnects and high-speed transistors used in radar and electronic warfare, so even a narrowly-targeted compound-level control reaches directly into defense-relevant semiconductor supply chains.

VAT export rebate cuts: a second, quieter lever on Chinese indium supply

Separately from the MOFCOM licensing regime, China has used the domestic value-added-tax export rebate as a tool to discourage exports of resource-intensive processed metals. On 15 November 2024, China's Ministry of Finance and State Taxation Administration announced the cancellation of export tax rebates for aluminum and copper products (effectively cutting the rebate from 13% to 0%) and a reduction from 13% to 9% for certain refined oil products, photovoltaic products, batteries and non-metallic mineral products, effective 1 December 2024 (english.www.gov.cn, 15 Nov 2024; USDA FAS GAIN report, Nov 2024). Indium metal itself was not named in the specific product lists published for the December 2024 rebate adjustment, which targeted aluminum, copper, refined oil, PV products, batteries and select non-metallic minerals rather than base or minor metals as a category (10100.com, summary of MOF/STA Announcement, 5 Dec 2024). No primary-source Chinese government notice identifying indium metal specifically for a VAT rebate cut was found in this review; claims to that effect should be treated as unconfirmed pending a specific MOFCOM/STA announcement naming indium's HS codes (8112.92, 2825.90, 2853.90).

Price Movement: A Decade High in Two Years

Per USGS MCS 2026, the U.S. warehouse (free-on-board) price averaged $351/kg in 2024 and an estimated $370/kg in 2025, peaking at $408/kg in June 2025. Reuters (9 Feb 2026) reported Rotterdam trading at $500–$600/kg, up more than 55% since September 2025, driven by speculative buying on a Chinese exchange and falling output from China and South Korea; Chinese customs data showed unwrought indium exports fell 23% month-on-month in December 2025 to 22.72 tonnes.

By 1 July 2026, Shanghai Metals Market assessed China's domestic 99.995% indium price at $775.34/kg, up 26.5% from $612.99/kg a month earlier — the first time in the tracked period that the Chinese domestic price moved above Western benchmarks (Rare Earth Mining, July 2026). Trading Economics' CNY-denominated series corroborated the move, showing indium at 5,450 CNY/kg on 3 July 2026 (Trading Economics).

The US Response: A $125M Stockpile Buy and a Korean Smelter Deal

26–27 August 2025 — DLA Strategic Materials issued a request for information for the potential acquisition of 222 metric tonnes of indium ingots for the National Defense Stockpile, alongside RFIs for tungsten, vanadium pentoxide and heavy rare earth oxides (Argus Media, 26 Aug 2025; HigherGov RFI record).

15 January 2026 — DLA Contracting Services Office–Columbus published solicitation SP8000-26-R-0011 on SAM.gov for two long-term Indefinite Delivery, Indefinite Quantity (IDIQ) contracts, sole-sourced under FAR 6.302-3, naming AIM Products LLC and Indium Corporation of America as awardees. The contracts carry a combined guaranteed minimum of $10 million and a maximum of $125 million over a three-year ordering period (27 Feb 2026 – 26 Feb 2029), with material delivered to the DLA Strategic Materials Scotia Depot in New York (SAM.gov solicitation SP8000-26-R-0011). Proposals closed 9 February 2026 after amendment.

The DLA Strategic Materials Broad Agency Announcement lists indium as a Priority 3 material for refining, processing and substitution research, alongside graphite, battery materials and PGMs, in a solicitation open through 30 January 2029 (DLA Strategic Materials BAA).

15 December 2025 — South Korea's Korea Zinc announced it will build a $6.6 billion ($7.4 billion including financing) critical-minerals smelter in Clarksville, Tennessee, jointly backed by the US Department of War (arranging roughly $2.15 billion with investors, including a conditional $1.4 billion investment) and the US Department of Commerce (a $210 million CHIPS Act award). The facility will process 1.1 million tonnes of raw material annually into 540,000 tonnes of finished product across 13 nonferrous metals — including indium, antimony, gallium and germanium — with phased commercial operations from 2029, built around Nyrstar's existing US zinc smelter (Korea Zinc press release, 15 Dec 2025).

Korea Zinc is the world's largest non-Chinese indium refiner, producing 90–150 tonnes/year at its Onsan smelter (roughly 9–11% of world supply), of which about 29% of total US indium imports and 90% of exports go to the US, Japan and Taiwan (Seoul Economic Daily, 9 Mar 2026; Chosun Biz). Canada's Teck Resources and Belgium's Nyrstar Auby are the other principal non-Chinese refiners: Teck's Trail, BC operation is "one of the world's largest integrated indium producers," recovering indium as a zinc-smelting co-product and supplying 1–10 kg ingots to ITO manufacturers (Teck Resources), while Nyrstar's Auby, France smelter has produced 99.998%-pure (4N8) indium since 2012, with historical capacity in the 45–72 tonne/year range (Nyrstar).

Indium's defense relevance runs through two compound semiconductors — indium antimonide (InSb) and indium phosphide (InP) — plus indium-based solders used in cryogenic and high-reliability electronics. Per USGS MCS 2026, indium tin oxide (ITO) coatings account for most global consumption, but the defense-critical volumes sit in these narrower compound and alloy applications.

1. Indium antimonide (InSb) in infrared detectors and missile seekers

InSb is a narrow-gap III-V semiconductor and the material of choice for medium-wave infrared (MWIR, 3–5 µm) photodetectors used in thermal imaging, forward-looking infrared (FLIR) systems and infrared-homing missile guidance. Per the SPIE reference volume on antimonide-based infrared detectors, InSb was identified in the 1950s as having the smallest bandgap of any known semiconductor at the time, and InSb focal-plane arrays remain central to the AIM-9 Sidewinder air-to-air missile family and other cooled staring-array thermal imagers; L3 Cincinnati Electronics fabricates 16-megapixel (4096×4096) InSb sensor arrays in current use in overseas combat zones. The DSIAC history of FLIR technology traces this lineage directly to the original development of indium antimonide detector materials and second-generation focal-plane arrays.

2. Indium phosphide (InP) in high-speed transistors for radar and electronic warfare

InP is the fastest transistor substrate technology in volume use: InP high-electron-mobility transistors (HEMTs) reach f_T/f_max of 350/700+ GHz, the highest of any semiconductor family, with the lowest noise figures (0.3–1.0 dB at 40 GHz), making InP the material of choice above 100 GHz for ultra-low-noise amplifiers, terahertz sources and radio-astronomy receivers (RF Essentials, GaAs/GaN/InP/SiGe comparison). Northrop Grumman operates a DoD trusted foundry fabricating InP heterojunction bipolar transistor (HBT) and pHEMT devices for military radar and satellite-communications systems (Microwave & RF, 2025). A 2018 EU RoHS exemption filing similarly noted that “GaAs is not a viable substitute for InP” in these applications and that InP is used in “military laser guidance systems including guided weapons and THz HBT transistor semiconductors in communications and decision-making applications” (ANIE Federation RoHS submission, 2018).

3. Indium solders in cryogenic and high-reliability electronics

Indium's low melting point (156.6°C) and ductility at cryogenic temperatures make indium-based solders and gaskets standard for vacuum seals, superconducting electronics, and detector packages that must survive thermal cycling to liquid-helium or liquid-nitrogen temperatures — the same cooled detector packages used in InSb focal-plane arrays and other space and missile-borne sensors. Per USGS MCS 2026, “some electrical components in data centers use indium-based solder alloys,” a commercial-technology parallel to the same low-temperature solder role in defense cryogenics.

4. Indium gallium arsenide (InGaAs) on InP substrates for night vision and LIDAR

InGaAs photodiode arrays grown on InP substrates are the standard detector for short-wave infrared (SWIR, 0.9–1.7 µm) imaging, used militarily for covert surveillance, active laser pointing and tracking, and laser radar (LIDAR), and for imaging the near-infrared laser designators and rangefinders used across NATO forces (640×512 InGaAs focal-plane-array camera study).

Indium is recovered almost exclusively as a byproduct of zinc smelting from the mineral sphalerite, with indium content in zinc ores typically under 100 parts per million (USGS MCS 2025). World refinery production and capacity in 2025 was concentrated in six countries:

Source: USGS MCS 2026.

US import sources: from 8% Chinese share to a Korea-Japan-Canada-led map

The United States imported 250 tonnes of unwrought indium and indium powders in 2024 (100% import-reliant), valued at approximately $85 million (USGS MCS 2025). Over 2020–2023, the US import mix was Republic of Korea 29%, Japan 18%, Canada 14%, Belgium 9%, other 30%, with China averaging just 8% — but Chinese share spiked to 25% of US indium imports by September 2024 ahead of the Section 301 tariff and MOFCOM control taking effect (USGS MCS 2025). Korea Zinc alone states it supplies 29% of total US indium imports (Seoul Economic Daily).

China's exports: Korea and Malaysia, not the US, are the primary destinations

China exported 347 tonnes of indium in the first nine months of 2024 (essentially flat year-on-year), split Republic of Korea 74%, Malaysia 10%, United States 10%, while importing 180 tonnes over the same period — underscoring that Chinese refined indium flows mainly to other Asian processing hubs rather than directly to the US (USGS MCS 2025). By December 2025, Chinese customs data showed unwrought indium exports falling 23% month-on-month to 22.72 tonnes, and September 2024-to-September 2025 exports down 72% year-over-year per Asian Metal (USGS MCS 2026; Reuters).

South Korea's own China dependency is rising even as it supplies the US

Korea Zinc supplies the US, Japan and Taiwan, but South Korea's own indium imports have grown more China-dependent: China's share of South Korean indium imports rose from 44.1% in 2015 to 94.2% in 2025, with South Korea importing $86.5 million of indium in 2025 (The Diplomat, 15 Jun 2026). This reflects Korea Zinc's own reliance on Chinese zinc concentrate and indium-bearing intermediate feedstock even while it refines and re-exports finished 4N8-purity metal to Western buyers.

EU classification: indium was dropped from the Critical Raw Materials list in 2023 — not added as "Critical (non-Strategic)"

Indium appeared on every EU Critical Raw Materials list from 2011 through 2020, but it was removed entirely when the European Commission published its updated CRM and Strategic Raw Materials lists alongside the Critical Raw Materials Act in March 2023 — the opposite of being reclassified as "Critical but not Strategic." The 2020 CRM list explicitly included indium (European Parliament Research Service, 2023), but the official Annex I (Strategic) and Annex II (Critical) lists attached to COM(2023) 160 do not name indium at all (CRM Act Annexes I–II, European Commission; EU Critical Raw Materials list, JRC Raw Materials Information System). The Commission's stated rationale was that EU production of refined indium (via Nyrstar Auby in France and other zinc smelters) now exceeds EU consumption, pushing its import-reliance and supply-risk scores below the CRM threshold (IEEP, "Circularity and the European Critical Raw Materials Act," 2023).

The removal proved controversial. An industry association representing indium, tellurium and rare-metals producers formally petitioned the Commission to reverse the decision, arguing indium's role in ITO for displays and CIGS solar cells warranted restoring it to both the Critical and Strategic lists (IMAT e.V. position paper on indium as a CRM, May 2023). A 2026 EU Court of Auditors special report on critical raw materials policy later flagged the same gap, noting that "tellurium and indium, deemed highly critical for the energy transition, are notably absent from current EU lists, despite appearing on the lists of five and six of the analysed [member state] countries, respectively" (European Court of Auditors, Special Report 04/2026).

Correction to conventional shorthand: indium is not currently on the EU's Strategic Raw Materials list or its Critical Raw Materials list as of the 2023 designation, which remained in force through mid-2026. Any reference to indium as "EU CRMA Critical (non-Strategic)" describes its 2011–2020 status, not its post-2023 classification — a distinction with real regulatory consequences, since only Annex I/II materials trigger the CRMA's benchmarking, permitting and stockpiling provisions. Watch: the Commission's next scheduled CRM list update, and whether the 2026 Court of Auditors findings prompt indium's re-inclusion.

1. ITO for LCD/OLED transparent conductors: the demand anchor

ITO thin-film coatings are "primarily used for electrically conductive purposes in a variety of flat-panel displays — most commonly liquid crystal displays (LCDs)" (USGS MCS 2026). Independent market research estimates the global ITO market at USD 1.84–1.92 billion in 2025–2026, growing at a compound annual rate of roughly 4.2% through 2031 (Mordor Intelligence, Indium Tin Oxide Market, 30 Jan 2026), while a separate estimate puts the high-purity ITO sputtering-target sub-segment at an average price of about $380/kg with roughly 18,000 tonnes of global target sales volume in 2025 (Intel Market Research, ITO target market, 2026). ITO is also used industrially as a coating on data-center optical fibers and cables to improve signal transmission, a commercial parallel to its display role (USGS MCS 2026).

2. CIGS thin-film photovoltaics: a real but shrinking end use

Copper indium gallium (di)selenide (CIGS) thin-film solar cells use indium as a core absorber-layer constituent. Solar Frontier (Japan), historically the largest-volume CIGS manufacturer, operated its Kunitomi factory — described as one of the world's largest thin-film solar plants, capable of ~112,000 modules/week — using a copper-indium-gallium-selenide variant (CIS) process; the company has stated its panels contain roughly 5% indium content, most of which is recycled manufacturing scrap, and has partnered with IBM on research to substitute copper or zinc for indium in future cell generations (Renewable Energy World, 2 Sep 2021). Avancis (Germany) and MiaSole (US/China, part of Hanergy) are the other principal commercial CIGS producers: Avancis set a CIGS thin-film module efficiency record above 20% in 2023 for its SKALA product line (AVANCIS press release, 17 May 2023), while MiaSole's flexible CIGS modules run at 15.7–17.5% aperture efficiency in commercial production, marketed for curved and metal-roof applications where crystalline silicon is impractical (MiaSole, FLEX Series product benefits). The U.S. Department of Energy notes that commercial CIGS module efficiencies typically run 12–14% even though laboratory cells have exceeded 20% (a 23.64% CIGS cell efficiency record was set in 2024), reflecting the technology's persistent lab-to-fab efficiency gap versus crystalline silicon (US DOE, Copper Indium Gallium Diselenide overview). CIGS remains a minority share of global PV shipments, which are overwhelmingly dominated by crystalline-silicon technology; indium's role here is real but has not scaled to rival ITO demand.

3. Low-melting-point In-Sn solders for optoelectronics and electronics assembly

Indium's low melting point (156.6°C) supports indium-tin (In-Sn) and other indium-bearing solder alloys used where process temperatures must stay below those tolerated by standard tin-lead or lead-free SAC (tin-silver-copper) solders — including optoelectronic component assembly, temperature-sensitive photonic packages and some data-center hardware. USGS notes "some electrical components in data centers use indium-based solder alloys" (USGS MCS 2026). Indium Corporation, one of the two firms holding the DLA's sole-sourced National Defense Stockpile supply contracts (see Section 3), is among the largest global manufacturers of indium-containing solder alloys, solder preforms and fluxes for electronics and optoelectronics assembly.

4. III-V compound semiconductors: InP, InAs and InSb for RF, infrared and quantum applications

Beyond ITO, indium's highest-value-per-kilogram use is as a constituent of III-V compound semiconductors. Indium phosphide (InP) underpins high-speed transistors and laser diodes for optical communications and data-center interconnects, and AI-driven demand for specialized chip materials is expected to increase InP consumption further (USGS MCS 2026). Indium arsenide (InAs) and indium antimonide (InSb) are narrow-gap semiconductors used in infrared photodetectors, thermal imaging and, in InSb's case, missile-seeker focal-plane arrays (detailed in Section 4). Research-stage InAs and InSb quantum dots and nanowires are also active substrates in quantum-computing and single-photon-detector research, an emerging, still pre-commercial demand vector not yet reflected in USGS consumption statistics.

No official end-use percentage breakdown is published by USGS for indium (unlike some other minor metals); USGS states only the qualitative ranking (ITO as the largest use, followed by alloys/solders, compounds, electronics/semiconductors, and research). Widely cited figures putting ITO demand above 55–60% of consumption derive from industry/consultancy estimates (e.g. SCRREEN, Roskill-style studies) rather than a current USGS statistical breakdown, and should be treated as directionally consistent with, but not identical to, government data.

1. Why ITO targets, not consumer products, are the recycling feedstock

Only about 30% of the indium in a planar ITO sputtering target is actually deposited onto the display substrate during manufacturing; the remaining ~70% remains in the spent target and surrounding chamber residues, which are collected and sent back for reprocessing (SCRREEN EU CRM factsheet, indium; ScienceDirect, closed-loop ITO target recycling study). Because this waste stream is generated at the point of manufacture — concentrated in a handful of large ITO-fabrication and display plants in Japan, China and South Korea — recovery economics are far better than for diffuse, low-concentration indium in discarded consumer electronics. Estimated recovery efficiency from spent targets ranges from 60% to over 70% of the indium contained in the starting target (NREL, The Availability of Indium, 2016). By contrast, end-of-life recovery from discarded LCD panels and other consumer goods is "nonexistent" at commercial scale, per a peer-reviewed materials-flow study, making pre-consumer ITO-target reclaim effectively the entirety of secondary indium supply today (Ciacci et al., Journal of Industrial Ecology, 2018).

2. Recycling's estimated share of supply: roughly half, though current official data are thin

A widely cited academic estimate states that "about half of the indium is from the secondary resource at present," and that spent ITO targets are "one of the most promising secondary resources," noting that almost 70% of ITO waste generated during manufacturing is technically recoverable (Zhang & Wu, Resources, Conservation and Recycling review, 2015, citing Kang et al. 2011). A separate NREL life-cycle study similarly found that recycled indium "represents recycling of manufacturing wastes rather than recovery from end-of-life products," with roughly 84% of that recycled tonnage occurring in or near manufacturing centers in Japan, South Korea and China (NREL, The Availability of Indium, 2016). However, USGS MCS 2026 states explicitly that "there were no readily available recycling or end-use data available for indium" for the current reporting year, and that while "indium-containing scrap was recycled domestically," the specific tonnage recovered was not published (USGS MCS 2026). The ~50% secondary-supply figure should therefore be read as an industry/academic estimate, not a current, government-verified statistic.

3. The recycler roster: Umicore, JX Nippon Mining & Metals, Indium Corporation, Asahi Pretec

Why it matters for ESG framing: because recycling is concentrated in the same Japan/China/Korea manufacturing clusters that dominate primary ITO production, indium's circular economy is largely closed-loop and industry-internal rather than driven by public-sector collection schemes (unlike EU WEEE-style consumer electronics recycling mandates, which the EU's own analysis notes have struggled to capture indium because small LCD-containing products are difficult to collect and dismantle economically) (Umicore/MMTA, 2010). There is no LBMA- or OECD-style responsible-sourcing standard specific to indium; sourcing due diligence for indium is typically folded into broader smelter-level conflict-minerals and ESG programs at the parent zinc/lead operations (Korea Zinc, Nyrstar, Teck, Glencore) rather than a dedicated indium chain-of-custody framework.

A compact chronology of the events that moved indium from a niche display-industry input to a named priority material in US stockpile planning. Each entry links to the primary record.