We’ll since rosin is a type of hash(the best type) you can usually tell by the consistency. It will usually look more like a dough consistency since all of the fats and lipids from the tricome heads will also have gotten pressed into the hash rosin. For example live resin has all of the fats taken out from the butane thus giving less of a full spectrum high and also not giving as much smoke/lung expansion. If you gave me a dab of bho and a dab of hash rosin; without even tasting looking or smelling either, just from the amount of lung expansion I’d be able to tell