To control the residual stresses in glass by controlled heating at, and cooling from, a suitable temperature.

Technical definition of the stress condition of ordinary glass.

Process designed to eliminate or limit stresses to glass by submitting the glass to strictly controlled cooling in a special oven known as a ‘lehr’.

Temperature at which the viscosity of the glass is approximately 1013 poises. At the annealing point of glass, internal stresses are substantially relieved in a matter of minutes.

A type of security glazing designed to resist manual attack and to delay access to the protected space for a short period of time.

See edge blocks

Glass with an uneven surface texture and bubbles inside, produced by using antique methods in order to obtain the appearance of glass made before the development of industrial processes.

Period of time during which a sealant can be effectively applied to a joint. The timing is from completion of mixing and could be affected by temperature, humidity or a combination of both.

The result of removing sharp edges.

A design developed primarily for reproduction.