Nice shot. I think they could use more contrast. An easy way to make it negeative in photoshop is to invert it, (ctrl+i). If you duplicate the layer and invert it, and then set its blend mode to color, you'll just invert the colors, which is also interesting.
Thanks Matt. I tried to get some more contrast via curves layer, but I just kept losing all the detail in the sculpture (what there is of it anyway). I even tried to mask off the sculpture in that layer, but I couldn't get rid of the halos it created. Any ideas? Feel free to edit and post (as long as you tell me what you did!) if you like.