# Perlite: Characteristics

The volcanic glass that pops like popcorn

Source page: https://www.materialinsights.org/commodities/perlite/characteristics/

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 4.6 Mt (2025e, USGS); 5.0 Mt in 2024 (World Mining Data) | China 1.5 Mt, Turkey 1.4 Mt, Greece 0.84 Mt and the US 0.46 Mt (processed crude sold) in 2025; these four made 92% of world output. | USGS MCS 2026; World Mining Data 2026 |
| **Inventory and stock levels** | not published; no exchange or strategic stocks | Stocks are crude ore at mines and ports and crude feed at expansion plants. Expanded perlite is too bulky to store in large volumes. No government stockpile. | USGS MCS 2026 |
| **Capacity utilisation** | not published | US mines produced 730,000 t of crude ore but sold 460,000 t of processed crude in 2025, and 53 expansion plants in 29 states processed it (USGS). No utilisation ratio is reported. | USGS MCS 2026 |
| **Geographic and producer concentration** | China about 33%, top-3 (China, Turkey, Greece) about 81%, HHI about 2,400 (USGS 2025); WMD HHI 2,254 (2024) | Greece and Turkey are the main exporters; Greece supplied 94% of US imports in 2021-24. Imerys and Dicalite lead company supply; volumes not published. | USGS MCS 2026; World Mining Data 2026 |
| **Supply elasticity** | moderate: expansion plants can be added in about a year; new mines take longer | Deposits occur in volcanic regions and resources are large in the US West, Greece and Turkey (USGS). Expansion capacity sits near customers and is quick to add. | USGS MCS 2026 |
| **Project pipeline and CapEx** | not published | No new capacity totals found. Consolidation: Imerys completed purchase of three diatomite and perlite assets in France and Italy in January 2025 (USGS). | USGS MCS 2026 |
| **Logistics and export flows** | perlite and vermiculite exports $208 million in 2024; Turkey 19.9%, South Africa 19.9% (vermiculite), Greece 15.0%; US took 21.2% of imports | Dense crude ore ships in bulk vessels from Milos (Greece) and Turkish Aegean ports, then is expanded near customers. Expanded perlite weighs about 40-140 kg/m3, so it cannot bear long freight. | UN Comtrade 2024; USGS MCS 2026; Perlite Institute |

#### Material characteristics Industrial mineral

Perlite is a volcanic glass with 2-5% bound water. Heated quickly, it pops like popcorn, expanding up to 20 times into a light, white, porous granule. Value depends on how well the crude expands, which is set by its water content and chemistry, and on the density, particle size and thermal conductivity of the expanded product for insulation, horticulture and filtration.

| Property | Value / specification | Why it matters | Source |
|---|---|---|---|
| **Expansion ratio** | up to about 20 times original volume (average about 12 times) | Higher expansion means more product volume per t of crude shipped | USGS MCS 2026; Perlite Institute |
| **Bulk density (expanded)** | about 40-140 kg/m3 | Lower density gives better insulation and lighter plasters | Perlite Institute |
| **Combined water (crude)** | about 2-5% (indicative) | The water turns to steam and drives expansion | Industry literature (indicative) |
| **Chemistry** | about 70-75% SiO2, 12-15% Al2O3, alkalis 6-9% (indicative) | Sets softening point and expansion behaviour | Industry literature (indicative) |
| **Thermal conductivity (expanded)** | about 0.04-0.06 W/m K (indicative) | Low conductivity suits insulation and cryogenic uses | Industry literature (indicative) |
| **Particle size and permeability (filter aids)** | graded filter-aid permeabilities comparable to diatomite (indicative) | Competes with diatomite for beer, juice and sugar filtration | USGS MCS 2026 (substitutes) |

## Other sections

- [Summary](https://www.materialinsights.org/commodities/perlite/index.md)
- [Overview](https://www.materialinsights.org/commodities/perlite/overview/index.md)
- [Correlation](https://www.materialinsights.org/commodities/perlite/correlation/index.md)
- [Extraction](https://www.materialinsights.org/commodities/perlite/extraction/index.md)
- [Production](https://www.materialinsights.org/commodities/perlite/production/index.md)
- [Stocks](https://www.materialinsights.org/commodities/perlite/stocks/index.md)
- [Cycles](https://www.materialinsights.org/commodities/perlite/cycles/index.md)
- [Trading](https://www.materialinsights.org/commodities/perlite/trading/index.md)
- [Movement](https://www.materialinsights.org/commodities/perlite/movement/index.md)
- [Criticality](https://www.materialinsights.org/commodities/perlite/criticality/index.md)
- [Emissions](https://www.materialinsights.org/commodities/perlite/emissions/index.md)
- [Relationships](https://www.materialinsights.org/commodities/perlite/links/index.md)