Iodine: Characteristics
The heavy atom that makes X-ray contrast work
What this tab covers The supply and physical characteristics of the commodity. Supply: current production, inventories and stocks, capacity utilisation, geographic and producer concentration, how fast supply responds to price, the project pipeline and capital spending, and logistics and export flows. Material: the physical and chemical properties that set its grade, price and end uses (for example purity and conductivity for metals, API gravity, sulfur and energy content for fuels, moisture, protein and fibre quality for crops).Supply volume characteristics
| Characteristic | Figure | What it means | Source |
|---|---|---|---|
| Current production volume | about 34,000 t (2025e, excluding US output, which is withheld); 33,000 t in 2024 | Chile made 23,000 t and Japan 9,000 t in 2025. Three Oklahoma companies also produce, and China and Uzbekistan produce but do not report. | USGS MCS 2026 |
| Inventory and stock levels | not published; no exchange or government stocks | There is no exchange and the US holds no government stockpile. Stocks sit with producers and converters as drums of prills. World demand of about 40,000 t expected in 2026 (SQM) means a month of consumption is roughly 3,300 t (derived). Secondary recovery of about 5,000 t a year (Roskill, 2012) acts as a partial buffer. | USGS MCS 2026; SQM 4Q2025 results; Roskill 2013 |
| Capacity utilisation | not published as a ratio | SQM sold 14.5 kt of iodine and derivatives in 2025, and a leading Chilean producer planned 4,000 t a year of new capacity (USGS 2026). SQM's 2021 report cited a 13,000 t a year capacity target at Nueva Victoria and a prilled-iodine plant of 11,000 t a year. Japanese brine output is capped by gas production and subsidence limits rather than plant capacity. | USGS MCS 2026; SQM 4Q2025 results; SQM Sustainability Report 2021 |
| Geographic and producer concentration | Chile about 68%, top-3 (Chile, Japan, Turkmenistan) about 97%, HHI about 5,400 (2025, excluding US); SQM about 37% of world demand | Derived from USGS 2025 country output, excluding the US. SQM's share is 14.5 kt against about 38.8 kt of demand. Chile also held 63.5% of world export value in 2024. | USGS MCS 2026; SQM 4Q2025 results; UN Comtrade 2024 |
| Supply elasticity | low short-run; moderate long-run (Chilean caliche expansions take about 2-4 years) | Japanese, US and Central Asian iodine is a by-product of gas and brine, so it barely responds to price. Chilean caliche producers are the only swing source: SQM, ACF, Sirocco and Bullmine added about 5,000 t a year of capacity in 2013-2017 after the 2011 price spike, and prices then fell about 18% a year. | USGS MCS 2026; CRU 2018; Roskill 2013 |
| Project pipeline and CapEx | about 4,000 t a year of new Chilean capacity planned; US Oklahoma plant additions | A leading Chilean producer planned to add 4,000 t a year (USGS 2026). One US producer opened an eighth Oklahoma plant and raised output about 11% in H1 2025. Project CapEx is not published. | USGS MCS 2026 |
| Logistics and export flows | most output is traded: world export value $2.26 billion in 2024; Chile 63.5% of exports, China (24.3%) and India (13.1%) the top importers | Prills move in drums or bags by container from northern Chilean ports (Iquique, Tocopilla area) and from Japan. Belgium (15.8% of exports) re-exports derivatives. Volumes are small, so freight is minor; the chokepoint is Chilean water and permitting, not transport. | UN Comtrade 2024; USGS MCS 2026 |
Material characteristics Industrial mineral
Iodine is sold as near-pure prills or flakes and then turned into compounds. What matters commercially is purity, because medical uses demand pharmacopoeia grade, and iodine's heavy atom, which absorbs X-rays and makes contrast media work. It sublimes easily and is corrosive, so form, packing and moisture affect handling. Buyers pay for consistency of purity and particle form, not for bulk properties.
| Property | Value / specification | Why it matters | Source |
|---|---|---|---|
| Purity / grade | Crude prilled iodine typically at least 99.5% I2; USP/Ph. Eur. iodine at least 99.8% (prill basis used in Roche et al. 2023) | Pharma and contrast-media makers need pharmacopoeia grade; lower grades go to feed and industrial uses | USP/Ph. Eur. monographs (indicative); Roche et al. 2023 |
| Atomic number and X-ray absorption | Z = 53; K-edge about 33 keV | Strong absorption at diagnostic X-ray energies is why organic iodine compounds are the standard CT contrast agents | Standard physical data (indicative) |
| Melting and boiling point | Melts about 114 C, boils about 184 C; sublimes at room temperature | Losses and corrosion in storage; shipped sealed in lined drums | Standard physical data (indicative) |
| Density | about 4.9 g/cm3 (solid) | High value per tonne and dense cargo, so freight is a small share of price | Standard physical data (indicative) |
| Impurities | Limits on non-volatile residue, chlorine and bromine (halogens) and moisture set by grade | Halogen impurities interfere with organic synthesis of contrast agents | USP/Ph. Eur. monographs (indicative) |
| Physical form | Prills (granules) or flakes | Prills flow and dose more easily in derivative plants | SQM product literature (indicative) |