This is a strong contender in the Game Jam, perfect blend of a good concept and excellent execution. I think tracfacsam is 100% right, this would do great as a mobile game, the vertical screen but even more so the "tap" control would be even better than using a mouse IMO.
There are two things I would like to have:
1. An indicator of how many clicks I have remaining (maybe its there and I'm just missing it) Okay yep I'm seeing this now
2. More time to fall before I go into the "final fall" - again, maybe I just missed it, but there were several times where I thought I still had clicks left, and was strategically letting the pickaxe fall to hit a dynamite or diamond, but then entered freefall. Might just be me not realizing I was out of clicks though.
Again, I want to emphasize how enjoyable this is, out of the 10 or so jam games I've played so far, this one stands out as the one that should be made into a full game, especially since I think it works perfectly as a mobile game. Congratulations on a job well done!
(High score: 1522 2518)