A study was made of the amount of glassy bond present in a typical whiteware body after various heat-treatments. Petrographic methods, with polished sections and powder mounts, were used for these determinations.
The results obtained by both methods and by independent observers agreed very well. With the higher firing temperatures, the amount of glass increased and the number of crystals decreased. Pore space diminished as the temperature was raised to the maturing temperature; above that point the pore volume increased.