Variety and graphics are nice, but gameplay is really shallow.
Main point of clicker games is to give the player a sense of accomplishment by allowing them to gain power in geometric progression. This game doesn't allow for proactive progression and upgrades your gear automatically. That would be something, but it seems the better the pickaxe is, the worse it is at doing it's job. Cracking the same stones takes longer the more you play, which doesn't feel right.