Laboratory Production of Amorphous Silicates

Abstract

This is a report on a technical subject, namely how to get a silicate into an amorphous state. Usually, the reverse process, i.e. to crystallize an amorphous material, takes place by itself due to the combined action of temperature and time and thus does not present experimental problems. Because of its spontaneous decay, the amorphous state is metastable and the conversion to the crystalline phase at a given temperature may take seconds or billions of years depending on the activation energy involved. For the silicates which are of interest here, the transition takes place within a reasonable amount of time at temperature in the order of 500 to 1000°C.