because for some reason it doe extra damage?
They are vulnerable to Force damage ... wich means any Force damage (wich Eldrich Blast is) is doubled for them.
Many materials is ... walls, statues, petrified persons, crystals, etc.
Since patch 6 not all of them showing that vulnerability when you inspect them tho. :-/
As for gold amount you get from their shards ...
I never managed to get more than aproximately 2000g ... its not bad, but nothing earthsaking i would say.
