Came across this today in an attic. At first I thought it might be ploypearl but when touched it turned to powder. It was spread throughout.
Any idea what this might be?
Perhaps it’s expanded polystyrene (EPS) beads?
Looks like EPS beads to me.
EPS beads shouldn’t turn to powder.
So what are your thoughts?
any chance it’s this inspected a nursery supply with residence, they’d used expanded gardener’s grade
It will be a gritty dust when crushed between fingers
I’d be as concerned about the stained material and the bleached kraft paper. I didn’t know attic varmints hiked their leg 
EPS will be around longer than most of us even when buried. I’ll find pieces of it that have been turned in the flower bed from 20+ yr EIFS jobs. Wash them off and they’re good as new.
You know I think it is perlite. It turned into a gritty dust and looked just like what is shown on the perlite site.
I was thinking perlite also but can’t blow up pictures from the threads for a better look… so didn’t venture a guess other than it didn’t sound like EPS beads.