I think this is the visual you are looking for:
From @Sibelios response in this thread:
That table was accurate from patch 0.35 up until these latest changes. I’m not sure what chapters drop what with the latest change as I had already completed 5 playthroughs, one with each class.
I hope the reworked crystals are retrospectively awarded to those who had already completed the chapters across 1-5 classes, since after 5 playthroughs players are left in limbo for maybe 6 months until luck chances them enough of each follower crystal to evolve many from Epic to Legendary.
Our previous expectation was that more classes were to be added to the game, and those would bring with them more opportunity for follower crystals. Though they were expected to be added with the launch from Early Access, and evidently that didn’t happen.