Pumice: Emissions
A light footprint from digging and screening
What this tab covers The greenhouse-gas footprint of the commodity at a global level, split by lifecycle phase: extraction (or farming), refining and processing, movement, usage, and recycling or end of life. Intensities are per unit of product; the global total combines intensity with world output. Also covers other environmental impacts and the main levers to cut emissions. Emission intensity 0.02 t CO2e per t range 0.01-0.05 · cradle-to-gate; open-pit digging, crushing, screening and, for some grades, drying Global emissions per year 0.40 Mt CO2e per year 2025 · 0.02 t/t times 20 Mt; excludes deliveryPer t of crushed and screened pumice at the mine, cradle-to-gate; seaborne delivery shown separately. Intensity: ecoinvent-based values for quarried aggregates (indicative). Global total: Derived from USGS MCS 2026 (indicative).
Share of footprint by lifecycle phase
Extraction 50% Refining / processing 50%Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Extraction | about 0.005-0.01 t CO2e/t | 50% | diesel loaders and trucks | soft, shallow deposits need little blasting | Indicative |
| Refining / processing | about 0.005-0.03 t CO2e/t | 50% | crushing and screening power; fuel for drying wet grades | fines handling causes local dust (USGS) | Indicative; USGS MCS 2026 |
| Movement | about 0.03-0.08 t CO2/t for Greece to the US east coast (roughly 8,000 km) | – | bulk carriers emit roughly 3-10 g CO2 per tonne-km depending on size (IMO Fourth GHG Study 2020, indicative) | For exported pumice, shipping can exceed the production footprint; outside the boundary above | IMO Fourth GHG Study 2020 (indicative); route length approximate |
| Usage | avoided emissions when it replaces clinker or heavier materials | – | pozzolan use in blended cement; lightweight blocks | Each tonne of clinker replaced avoids roughly 0.8-0.9 t CO2 (GCCA, indicative) | GCCA (indicative) |
| Recycling / end of life | not applicable | – | Little to no known recycling (USGS) | pumice in concrete is crushed with it at demolition as aggregate | USGS MCS 2026 |
Other environmental impacts
Local dust from reject fines and land disturbance at open pits, mostly in remote areas (USGS).
Levers to cut emissions
- Use pumicite as a natural pozzolan to cut clinker in cement
- Source from the nearest deposit; freight is the largest footprint for traded pumice
- Electrify crushing and use solar drying where possible
India
India is not listed as a producer (USGS 2025), so its small imports for denim washing and cleaners carry a sea-freight footprint; India's cement industry relies on fly ash and slag rather than natural pozzolans.
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.