Great concept! I really like it. =)

A few suggestions:

• better lighting. The hand is too dark, and in trying to compensate for that, you've really accentuated the noise.

• include more of the map in the background. I'm not sure how you might accomplish this optically, since I'm not familiar with what kind of focal length a marble has. :P My gut feeling is to move both the marble and the camera farther away from the map, and use a longer focal-length lens on the camera. Just experiment and find out what works!

• make the marble a larger part of the composition. Moving the marble closer to the camera, or keeping it in the same relative position while using a longer lens, would accomplish this. (However, if you keep everything where it is and increase your lens's focal length, you will get even less of the map in your background, which is counterproductive to my previous point. Just keep experimenting!)

• a bit more sharpness would go a long way! If you use more light (flash or continuous light) then you can use a shorter shutter speed which may give you more sharpness. Or you may be limited by your lens. It's hard to tell since I don't know what gear you're using and how much this photo was cropped. Regardless, it's probably hard to improve the sharpness a lot inside the marble, because I doubt the marble is optical quality glass. But you can improve the sharpness of the marble's edge, and the edges of your daughter's hand.

Once again, really cool photo! If you decide to try again with some of these suggestions in mind, I would love if you PM'ed me with a link to your new take. =)