Tempered Glass
increases the strength of the glass approximately 4 times; however, the process makes the glass brittle and can warp its surface. The process involves heating the glass to approximately 1400 degrees, then chilling (quenching) it to 200 degrees within 2 minutes. Tempered glass, once tempered, cannot be re-cut without shattering. For this reason, all fabrication must be done before the glass is tempered.