Perlite is the generic name for a naturally occurring siliceous volcanic rock. We are manufacturing the Norlite ® Perlite in one of our special kilns at temperatures of more than 1000o C, whereby the original raw material is expanding up to 20 times its original volume, and we achieve a new product : a white, sterile granular. This expanded product is afterwards milled and create a Perlite filter aid.

Chemical CompositionPhysical properties of Perlite
SiO2 : 72-74%
AL2O3 : 13-14%
TiO2 : 0,06%
Fe2O3 : 0,6-0,7%
CaO : 0,2-0,75%
MgO : 0,1-0,26%
Na2O3: 3.0-4.0%
K2O : 4,78%
Organic substances: none
Inert Material: Max 1.0 ml/50gr.
Hygroscopicity: none
Colour: Very light white powder
Free moisture, max. 0,1%: 0.1 when leaving factory pH (of water slurry): 6-8 suspension 10%
Bulk density 100-170 kg/m³
Particle size: 5-50µ average
Softening temperature: 1100ºC
Melting point: 1350ºC
Solubility: Soluble in hot concentrated alkali and HF, moderately soluble (<10%) in 1 N NaOH. Slightly soluble (<3%) in mineral acids (1N). Very sightly soluble (<1%) in water or weak acids.
Beer soluble Iron (ppm) 15,0- = from 10-50

Trace elements %

ArsenikBariumBoronKlorinKromKopperGalliumBlyManganMolybdænSvovlTitanZirkon
< 0.001*<0.1<0.010.0005<0.0075<0.0015<0.05<0.001*<0.3<0.002<0.02<0.1<0.003
* By "Food Chemical Codex" method