Pyroceram is a material developed and trademarked by Corning Glass during the 1950s. Its development has been traced to Corning's work in developing photosensitive glass

Photosensitive glass

Photosensitive glass is a crystal-clear glass that belongs to the lithium-silicate family of glasses, in which an image of a mask can be captured by microscopic metallic particles in the glass when it is exposed to short wave radiations such as ultraviolet light. Photosensitive glass was first...

. Corning credits S. Donald Stookey

S. Donald Stookey

Stanley Donald Stookey is an American inventor. He has 60 patents in his name related to glass and ceramics, some solely his while others are jointly with others...

 with its discovery; while conducting research on photosensitive glass, Stookey noted that an accidentally overheated fragment of the glass resisted breakage when dropped.

The manufacture of the material involves controlled crystallization

Crystallization

Crystallization is the process of formation of solid crystals precipitating from a solution, melt or more rarely deposited directly from a gas. Crystallization is also a chemical solid–liquid separation technique, in which mass transfer of a solute from the liquid solution to a pure solid...

. NASA

NASA

The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 classifies it as a Glass-ceramic

Glass-ceramic

Glass-ceramics are polycrystalline material produced through controlled crystallization of base glass. Glass-ceramic materials share many properties with both glasses and ceramics...

 product.

After about 30 years of informal use as a standard in high heat (1000 degrees Celsius) applications, Pyroceram 9606 was approved as a certified reference material.