Yesterday someone gave me a small piece of what I think must be the weirdest, most meddled with "hashish" I've ever seen. I've just whizzed it up in boiling water and filtered it out of curiosity as I'm certainly not smoking it, but here are some of my findings:
Before dissolving:
It's very soft but doesn't stick together properly, so you can squash it but it cracks and it's hard to persuade it to reform. It's almost cake-like.
It has a slight salty (!) taste and a gritty texture if you dissolve some in your mouth.
Burns dirty, smoke doesn't smell like hash.
When dissolved:
There's something water-soluble in there as the water goes yellowy-brown straight away.
Rinsing it some more makes the water grey and cloudy.
Scum seems to float to the surface.
In the filter it looks grainy, almost like coffee grounds, which is not how even moderately contaminated hash behaves in these circumstances.
Squeezing it when wet doesn't make it stick together. It can be persuaded to do so but it sticks to everything when wet.
Annoyingly, now that I've handled it I can smell good hash on my fingers, so I suspect that that was one of the ingredients.
It seems that whatever the main contaminant is, it isn't water soluble.