Kyanite: Emissions
A furnace-lining mineral with no published footprint
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.Per t of kyanite concentrate or calcined mullite, cradle-to-gate. Intensity: none found. Global total: USGS MCS 2026.
Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Extraction | a few kg CO2e/t of ore moved (analogue); about 4 t of ore per t of concentrate at 25% grade | – | hard-rock open-pit mining with diesel haulage | comparable rock quarrying and crushing averages about 4.3 kg CO2/t (Mineral Products Association 2009 via BGS 2010), an indicative analogue | Virginia Energy 2023; MPA 2009 |
| Refining / processing | not published; calcining is the largest phase for kyanite | – | flotation and magnetic separation (electricity); kiln fuel to calcine kyanite to mullite | no carbonate is decomposed, so there is no process CO2, only fuel; andalusite needs no calcining | Virginia Energy 2023 |
| Movement | about 70 kg CO2e/t per 10,000 km by bulk ship (derived) | – | ocean freight from South Africa, Peru, France and the US to refractory plants | large bulk ship about 0.007 kg CO2e per t-km, road truck 0.178 (ERM for The Crown Estate, 2010) | ERM for The Crown Estate, 2010 (derived) |
| Usage | no direct emissions; enables steel, cement and glass furnaces | – | iron and steel take 60-70% of refractory use | longer-lasting linings cut refractory use per tonne of steel | USGS MCS 2026 |
| Recycling / end of life | recycling of spent refractories is insignificant today | – | spent linings are landfilled or reused as aggregate | USGS expects recycled refractory material to be used more often | USGS MCS 2026 |
Other environmental impacts
Beach-sand sources for sillimanite raise coastal erosion and illegal mining concerns; Tamil Nadu began recovery proceedings in 2025 against five companies.
Levers to cut emissions
- Use andalusite raw where possible, avoiding calcining fuel
- Recycle spent refractory linings into new refractories
- Electrify or switch calcining kilns to lower-carbon fuels
- Extend lining life, which cuts refractory demand per tonne of steel
India
India has 9.1 Mt of reserves but produced only 2,500 t in 2025 and relies on imported andalusite (79% from South Africa) for its steel industry's refractories, so most of its footprint is in imports and shipping (USGS 2026; IBM 2022).
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.