Originally Posted by AngryScot
those are cool, but you would have to have very good flame control so you don't burn the stuff or handles.
As long as the kettle was full, it wouldn't matter if the flame hit the silicone body. You can boil water in a plastic soda bottle as long as the flame only contacts where there is water on the other side - sounds crazy but it works - give it a try.
Silicone (or at least certain grades) are very heat tolerant - I've used silicone moulds to cast lead in the past.