This is based on Graham Stone’s work.
Temperatures are in degrees Celsius.
660 Bungs still out for casting.
710 Mould "curing" starts (molecular moisture being expelled).
820 Bas relief complete. Whiting gives off CO2
850 Glass flowing. Viscosity decreasing quickly. Common casting temperature
870 Fine mould/mold detail complete
900 Plaster moulds becoming very brittle
950 Un-reinforced plaster moulds no longer viable.
1100 Glass runny enough for sand casting and other manipulative techniques.
Based on Firing Schedules for Glass; the Kiln Companion, by Graham Stone, Melbourne, 2000, ISBN 0-646-39733-8, p24