Perlite Uses

perlite uses

what is perlite?

Perlite is formed during volcanic occurrences being the result of the hydration
of rhyolitic obsidian, a rock resulting of a sudden chilling (cool down) of molten lava.

This expansion is due to 2 to 6% combined water in the crude Perlite rock. When quickly heated to above 1600°F (871°C), the crude rock pops in a manner similar to popcorn, as the combined water vaporizes which accounts for the amazing lightweight and other exceptional physical properties of expanded Perlite.

Perlite is a generic term for naturally occurring silicious rock, not a trade name.
The distinguishing feature that sets Perlite aside from the other volcanic glasses is that when heated to a suitable point in its softening range, it expands from 4 to 20 times its original volume.

Pennsylvania Perlite is a Perlite Institue Member as well as OMRI Certified.
Click these links for more information on Perlite
www.perlite.org | www.omri.org.

Crude Form

Perlite is an amorphous crystal, which is unique in its chemical composition where there is almost no presence of crystalline silica. Perlite dates as far back as about fifty million years ago.

Crushed Form

The crude Perlite may range in color from transparent light gray to glossy black. Since Perlite is an amorphous natural glass, it is classified as chemically inert and has a pH of approximately 7.

Expanded Form

The color of expanded Perlite ranges from snowy white to grayish white. Expanded perlite can be manufactured to weigh as little as 2 pounds/cubic foot, making it adaptable for numerous applications.

Average Chemical Composition of Perlite

Element

Percentage

SiO (Silicone Dioxide)
74
A1O (Aluminum Oxide)
13
K2O (Potassium Oxide)
5
Na2O (Sodium Oxide)
3
Fe2O (Ferric Oxide)
1
Water
4
Total
100

Other Useful Characteristics

Softening Point
1600 - 2100°F (871 - 1090°C)
Fusion Point
2300 - 2450°F (1260 -1343°C)
Water Content in the Particle before Expansion
2 to 5%
pH
6. 5 - 7. 5
Refractive Index
1.5
Specific Heat
0.20
Specific Gravity Ore
2.2 to 2.4
Water
4
Color
White to Gray
Water Absorbtion, %wt.
200 - 600
Oil Absorption, gmsoil/gm
50 - 100
Bulk Densities of the Product
From 65.1 to 2lbs/cu ft
Wet Density, lbs/cu ft.
5.0 to 20.0
Solubility
<10% in 1 N NaOH & <3% in Mineral Acids
Particle Size US Mesh
4 to 325 depending on application