Is it such a bad idea to insulate my igloo with rockwool???

[Masako Morishita]

After reading some of the input on rockwool, is it really a no no to
insulate my igloo with this material???
Looking at the options , I thought, if I use a blanket of rockwool and a blanket
of regular fiberglass insulation like a sandwich and then vermiculite cement,
would that work????
At this point I'm all ears!!!!! Arigato!