I was talking to a person (lets say his name is Tim) that when Tim was a child he remembered in a grade school demonstration on this Starlite material (Starlite is a material claimed to be able to withstand and insulate from extreme heat, but the formula was lost when the inventor died.) along with some Tesla stuff. He got to participate in the demonstration, and he said the demonstration was performed by the British amateur chemist and hairdresser Maurice Ward and the stuff did as wiki said it did. 

He said they only thing that Wiki got wrong is that Ward said it was made from eggshells along with some other stuff and didn't remember any eggshell thin coating analogy in the demonstration. 

Does powdered eggshell in any way in an organic alloy foam state or otherwise produce heat shielding properties?

Why can't the formula be cracked or has it?