Tolerance

(+ or -

Oxides

Percentage Weight

Percentage Range)

Silicon Dioxide

66-75

1.00

Aluminum Oxide

 0-7 

0.50

Calcium Oxide

 5-15

0.50

Magnesium Oxide

 0-5 

0.50

Sodium Oxide

 8-18

0.50

Potassium Oxide

 0-4 

0.50

Iron Oxide

 less than 0.5

0.05

Chromium Oxide

 less than 0.1

0.02

Sulfur Trioxide

 less than 0.2

0.02

All other oxides

 less than 0.1

0.02

Organic Carbon

 less than 0.1

0.02

Moisture Content

 less than 0.5

0.05

(No caking with free-flowing fiberglass)

Loss on Ignition

 less than 1.0

0.10