may vary from shiny, where the glass is balanced, to matt where
excessive flux oxides may form visible, possibly lumpy, crystals.
The glaze represented
by the example model in the diagram might be runny at certain temperatures
and could be patchy with areas of clear glaze interspersed with
matt opaque areas where crystals have developed around the free
CaO molecules not bound with Al2O3 and SiO2 into glass structures.