PerlitePerlite is a naturally occurring siliceous rock which is sometimes referred to as volcanic glass. It is highly sorbent, so is widely used in hydrophonics, ceramics, horticulture, manufacture of lightweight construction materials (such as plasters, mortars and insulation), as well as in other industries where high sorptive properties are required.  Expanded Perlite is a white, ultra-low density mineral available in four grades to suit most applications.


Expanded Perlite is a volcanic aluminosilicate glass with an internal structure consisting of numerous tiny closed air cells.  It expands greatly under high termperatures. At 850 – 900°C, perlite softens and water trapped inside its structure escapes.  This causes the material to expand to many times its original volume, and its bulk density falls from around 1100 kg/m3 to around 10% of this figure, or even less. Expanded Perlite is white due to the reflectivity of the trapped bubbles.


Typical Chemical Analysis


SiO2 – 73%
Al2O3 – 15%
K2O – 5%
Na2O – 3%
Fe2O3 – 2%
CaO + MgO – 1%
Others – 1%
Organic Matter – Nil
Moisture – Nil (when packed)


Typical Physical Properties


Softening Point – 890-1100˚C
Fusion Point – 1280-1350˚C
Specific Heat – 0.20
Refractive Index – 1.5


The bulk density of expanded perlite depends on the grading of the product.  As a result, the poured bulk density ranges from 40 to 120 Kg/m3 and the compacted bulk density from 50 to 150 Kg/m3.


Particle Sizes Available


The following particle sizes are available: 0.015-2mm, 0.15-3mm and 2-6mm.
Perlite is sold in 100 litre sacks and 1250 litre bulk bags.


For further information or to buy,  please contact us.