In reply to Wide_Mouth_Frog:
> I've only had one day bouldering on Dartmoor back in 2006/07 and I can confirm that it is the possibly the roughest rock on earth. Maybe slightly less destructive than Hampi, though not by much!
There's an article in this isn't there - where is the world's sharpest rock?!
Dartmoor is a given, as is Hampi. Bishop is pretty bad, or good - depending on what you're into. Gabbro is rough, as opposed to sharp, so that's out. I'm sure there's some grim limestone venues that feature small/sharp crimps, but the fact that Dartmoor is literally coated with razorblades means that it trumps anything with an isolated sharp hold here or there...