Perlite Message In A Bottle

The basic requirement in glass raw materials is their consistency in both physical and chemical properties. The same guideline applies equally well for any new raw material which is destined to replace one of the materials already in use. This article introduces the use of a certain quality of "volcanic glass", namely perlite, as a glass raw material. It is used as a substitute for traditional feldspar as a source of alumina in amber glass production in a container furnace.