I picked up a set of MOHS test picks. They are handy to determine the hardness or softness of concrete.
Despite having ground a few slabs in my day I just learned that there are soft bond and hard bond diamond abrasives. That said, most of the pads, discs, and cups that I can find for sale do not specify if they are "soft bond" or "hard bond".
Is it safe to assume that if a disc doesn't specify if it has a "Soft Bond" then its a "Hard Bond"? Which is more common?