Architectural glass light in industrial factories. Annealed glass is glass without internal stresses caused by heat treatment, i.e., rapid cooling, or by toughening or heat strengthening. Glass becomes annealed if it is heated above a transition point then allowed to cool slowly, without being quenched. Float glass is annealed during the process of manufacture. However, most toughened glass is made from float glass that has been specially heat-treated. Annealed glass breaks into large, jagged shards that can cause serious injury and is considered a hazard in architectural applications. Building codes in many parts of the world restrict the use of annealed glass
Glass casting the solid glass object. This very immediate and dynamic method was pioneered and perfected in the 1980s by the Swedish artist Bertil Vallien. Kiln casting involves the preparation of a mould which is often made of a mixture of plaster and refractory materials such as silica. A model can be made from any solid material, such as wax, wood, or metal, and after taking a cast of the model (a process called investment) the model is removed from the mould. One method of forming a mould is by the "Cire perdue" or "lost wax" method. Using this method, a model