Gypsum: Characteristics
The water trapped in its crystals is the whole point
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 160 Mt mined (2025e), plus about 17 Mt of synthetic gypsum used in the US alone | World mine output was 160 Mt in 2025 against 162 Mt in 2024 (USGS); the WMD series puts natural gypsum and anhydrite at 218 Mt in 2024. Synthetic FGD gypsum and phosphogypsum add large volumes that most countries do not report. | USGS MCS 2026, Gypsum; World Mining Data 2026 |
| Inventory and stock levels | not published | Gypsum is cheap and plentiful, so nobody holds strategic stocks; the US has no government stockpile (USGS). Working stocks sit at quarries, ports and board plants. The largest physical stockpiles are phosphogypsum stacks at fertiliser plants, which are a waste problem rather than usable inventory. | USGS MCS 2026 |
| Capacity utilisation | US wallboard plants about 76% (26 of 34 billion sq ft, 2025) | Derived from US wallboard sales of 26 billion sq ft against panel capacity of about 34 billion sq ft at the start of 2025. Quarry utilisation is not published. | USGS MCS 2026 (derived) |
| Geographic and producer concentration | China 27.6%, top-3 (China, US, Iran) 46.4%; HHI 1,113 (2024) | Unconcentrated by country. Board making is concentrated in a few firms (Knauf with USG, Saint-Gobain, Etex, BNBM), but their gypsum tonnages are not published, so no top-5 company share is available. | World Mining Data 2026 via tile brief; company list from content tile |
| Supply elasticity | high for quarries; near zero for synthetic gypsum | New quarries are simple open pits that can open in a few years where permits allow. FGD gypsum depends on coal burn and falls as coal plants close, regardless of gypsum prices. Board plants take a few years to build. | USGS MCS 2026; Global Gypsum (2023) |
| Project pipeline and CapEx | growth led by Asian wallboard plants; India targets 9.9 Mt a year of FGD gypsum | USGS says increased wallboard use and new plants in Asia are lifting world production. India produced about 2.1 Mt of FGD gypsum with a target of 9.9 Mt by 2025-26 as power plants fit scrubbers. Capex figures per plant are not published in the sources used. | USGS MCS 2026; Global Gypsum (27 Jul 2023) |
| Logistics and export flows | export value $1.31 billion (2024); Oman 13.3%, Thailand 12.8%, Germany 12.3% | Low value per tonne (about $13/t at US mines) means gypsum moves by sea only from coastal quarries. Oman exported 11.2 Mt in 2023, 5.3 Mt of it to India. US imports of 6.8 Mt (2025) come from Spain, Mexico and Canada. Freight, not supply, is the bottleneck. | Comtrade 2024; Global Gypsum (Jan 2024); USGS MCS 2026 |
Material characteristics Industrial mineral
Gypsum is calcium sulfate dihydrate. Its value lies in the water locked in its crystals: heating drives most of it off to make plaster, which sets hard again when water is added, and the remaining water slows fire. In cement only purity and SO3 content matter. Buyers pay for whiteness and low salts in board and plaster, and for low moisture in freight.
| Property | Value / specification | Why it matters | Source |
|---|---|---|---|
| Purity | Pure CaSO4.2H2O; commercial rock often 80-95%, FGD gypsum typically at least 95% (indicative) | Higher purity gives stronger, whiter plaster and allows food and pharmaceutical grades | Eurogypsum/VGB FGD gypsum quality criteria (indicative); USGS |
| SO3 content | 46.5% in pure gypsum (stoichiometric) | Cement makers dose gypsum by SO3 to control setting time | Chemistry (CaSO4.2H2O) |
| Combined water | 20.9% by weight (stoichiometric); about three-quarters is removed by calcining to hemihydrate | Sets plaster yield and gives board its fire resistance, since this water must boil off before the board burns | Chemistry; USGS |
| Free moisture | FGD gypsum specified at no more than about 10% (indicative) | Wet gypsum costs more to ship and dry | Eurogypsum/VGB criteria (indicative) |
| Soluble salts (chloride, sodium, magnesium) | Chloride typically limited to about 0.01% for board (indicative) | Salts weaken the paper-to-core bond and cause efflorescence | Eurogypsum/VGB criteria (indicative) |
| Hardness and density | Mohs 2; density about 2.3 g/cm3 | Soft rock is cheap to quarry and grind | Mineralogical data |