This material is actually a transparent glass-ceramic manufactured by Schott Glaswerkes.

ROBAX® glass-ceramic has a thermal endurance far exceeding that of normal tempered glass. Tempered glass is generally limited to applications that do not exceed 500F. However, ROBAX® is designed to operate at temperatures ranging from minus 400F. to plus 1400F. 

Glass-ceramic was invented in the 1960s. Its thermal endurance and stability make it ideal for many products: from stove tops and cookware, to missile nose cones and astronomical telescope mirror substrates. Transparent glass-ceramic, introduced in 1970s, is much more difficult and expensive to make than ordinary glass. As a result, it also has a different appearance including color, surface texture, and some small bubbles or inclusions that are natural to its composition and have no effect on its strength or performance. 


We've placed a cutting torch below the ROBAX® and heated it until red-hot. Then cold water was poured on the glass from above - with NO breakage.

Because of its special composition and processing this unique material can withstand a quench into ice water from red hot temperatures. With ROBAX® Glass-Ceramic windows in your stove or fireplace, you can enjoy the fire view with the assurance the window has been designed with a superior margin of safety for your home and your family.

Normal Service Extreme Service Thermal Shock Coefficient of Thermal Expansion
1400 F. 1475 F. 1400 F. +1.6X10-7in./in./ F.

NOW .... One glass can supply all of your high temperature requirements. Unlike tempered glass, 1400 Glass-Ceramic is unstressed. It can easily be cut and finished using standard glass cutting tools.

Easily cut and sanded - even drilled. Will not shatter (like tempered glass).
Good strength. Fire to Ice without breaking.

This is an excellent replacement in most applications for any of the following glasses - PYREX®, BOROFLOAT® , TEMPAX® , VYCOR® , PYROCERAM® , and NEOCERAM® . Typical applications include--

Wood Stove, Pellet stove and Coal Stove Windows. Wood and Gas Fireplace Doors. Oven Door Windows. High-intensity Light Covers. Furnace Observation Windows. Barbecue Grill Windows. Spark and Flame Guard Panels.


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Last modified: 11/09/08