Firing polishing cast glass
Firing polishing cast glass can be tricky, depending on size and shape. The trick is to get to fire polish temp as quickly as possible (once past the risk of thermal shock) to allow the heat to “wet” the surface without penetrating the glass sufficiently to cause it to deform.
Cabochons, because they have rounded surfaces (not a lot of surface texture detail) should fire polish easily. Temperature will vary depending on glass and speed at which kiln heats. Try 1375 F to start and adjust accordingly.
Helios Kiln Glass Studio