If popcorn ceiling contains asbestos, then does it mean it's made out of vermiculite?
Vermiculite itself has not been shown to be a health problem or contain asbestos. However, some vermiculite insulation contained asbestos fibers due to it being extracted from a mine in Montana that had a natural deposit of asbestos which contaminated the Vermiculite. If used for popcorn ceiling, the asbestos wasn't purposely added but could have been left over from the Vermiculite mined in Montana.