Yea in part it’s whether the material will break down or off-gas. But I was also curious so I could shove a lump in my ultralight alu trangia copy to see how the flame goes.
My genuine trangia kit is still in the same bag probably manky after using last summer. Shows how much use that stuff gets.
https://www.bioethanol-fireplace.co.uk/ceramic-fibre-cotton---what-is-it-_6601.html
Hmm...