Glass cullet, 1960-1969

Mixture of raw materials, with cullet, for making glass

Cullet is broken or scrap glass, which is added to the batch as it melts more quickly than new ingredients, and therefore saves fuel, and also it is a method of recycling. Cullet usually consists of fragments of glass discarded during production although scrap glass, e.g. out-of-fashion glass, is also broken and included. Cullet may be the only ingredient in the batch, but generally constitutes 20-50% of the ingredients.