Pumice: Characteristics
Light, porous and gritty: what buyers pay for
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 20 Mt of pumice and related material (2025e) | Turkey made 9.7 Mt, then Jordan 1.1 Mt, Greece 1.0 Mt and Saudi Arabia 0.98 Mt. Many country figures include pozzolan and volcanic tuff. US output was 0.43 Mt. | USGS MCS 2026, Pumice and Pumicite |
| Inventory and stock levels | not published | No government stockpile exists (USGS). Pumice is plentiful and cheap, so stocks are working piles at pits and block plants. | USGS MCS 2026 |
| Capacity utilisation | not published | USGS reports 10 US operations producing 430 kt in 2025, about 43 kt each, but no capacity data. Output is set by local construction demand and freight costs rather than plant limits. | USGS MCS 2026 |
| Geographic and producer concentration | Turkey 48.5%, top-3 (Turkey, Jordan, Greece) 59%; HHI about 2,500 (listed countries, 2025e) | Moderately to highly concentrated by country. Producers are small and mostly private, so no company shares are published. | USGS MCS 2026 (derived) |
| Supply elasticity | high in the short run where deposits are permitted | Open pits with simple crushing can expand within a season. Long-run limits are land access and permits: USGS notes legal challenges and public land designations in the western US. | USGS MCS 2026 |
| Project pipeline and CapEx | no large projects published | Interest in natural pozzolans to cut clinker in cement could raise demand for fine pumicite. No named capacity projects or capex figures were found in the sources used. | USGS MCS 2026; content tile |
| Logistics and export flows | small share traded; Greece supplied about 80% of US imports (2025) | US imports were 64 kt in 2025, against 480 kt consumption. Freight sets how far pumice can travel; Aegean island quarries ship directly to Europe and US east and Gulf coasts. | USGS MCS 2026 |
Material characteristics Industrial mineral
Pumice is volcanic glass frothed with gas bubbles, so it is light, porous and mildly abrasive. Buyers pay for low bulk density and strength in building blocks, uniform grain size in abrasives, and reactive silica for pozzolan use in cement. Low value per tonne means local deposits win over better ones far away.
| Property | Value / specification | Why it matters | Source |
|---|---|---|---|
| Bulk density | ASTM C330 lightweight aggregate limits: coarse at most 880 kg/m3, fine at most 1,120 kg/m3 | Light blocks and concrete cut structural loads and transport costs | ASTM C330 |
| Porosity | often 60-90% voids; lumps can float on water (indicative) | Gives insulation, absorbency and drainage in horticulture | USGS; mineralogical data (indicative) |
| Chemistry | typically 60-75% SiO2 with 10-15% Al2O3 (indicative) | Reactive glassy silica makes fine pumicite a pozzolan | Mineralogical data (indicative) |
| Pozzolanic activity | ASTM C618 Class N: SiO2+Al2O3+Fe2O3 at least 70%, strength activity index at least 75% at 7 or 28 days | Qualifies pumicite to replace part of the cement in concrete | ASTM C618 |
| Hardness | Mohs about 6 (indicative) | Hard enough to abrade, soft enough not to damage denim or skin | Mineralogical data (indicative) |
| Grain size | sized fractions from lumps for stone washing to fine powders for cleaners (indicative) | Each use pays for a specific size range | USGS; industry practice (indicative) |