Nice Idea

like your idea,
you should make the rocks worth more though, at least three, 1 can buy almost nothing. another key idea in tycoon games is the ability to literaly build stuff- adding placing would is essintial, the game also needs something for the players to do while they mine- such as searching out new places to build in the least, or watching their guys find ore- make the guys move, not just stand and mine forever, as I got tired of watching him at about 20 score, and then started writing this- I supose its more of a review so Ill copy and paste it in that after Im done. Anyway- dont let this discourage you, as I said before, you have a good idea going, however an idea isnt enough, and improvement is mandatory for this to be a success. Now This is a game that actualy may very well succede as well- if it is made better. I can tell that you are somewhat new to game maker simply by seeing your sprites, seeing as that most of the people here use game maker, and had to learn from something, the chances that they look at your game and recognise your sprites as being in the starter set and thinking that you are a noob are infendesimately huge. The first thing I would do If I were you would be to make, or have made for you, a new sprite set, and by have made I mean go to the yoyo games community and look for people to help you with sprites - spriters. And If you can find someone to make music, if you cant use freeplay music. (if freeplaymusic.com doesnt work try google) Also dont use large tacky images, as they are an eyesore. Finally my last suggestion is to change your game pictures, to the actual gameplay, not just a cool image.

Again I must add that this isnt meant to discourage you, but to improve your game(s) and such. Id be happy to answer questions if you need that, so just PM me. I do believe this could have a nice turnout.