Okay, from reading this, I get it is supposed to be a cave. Sorry for that I have to knock you. Been caving as a sport/hobby for several years. You kinda need to think more in the lines of cones both on the floor and ceiling. Some can and do join equalling columns. The typical shape is more of an isosolean sp? But that has been my experience, mind you though I have seen several that came out of the walls, floors, and ceiling that did all sorts of strangeness. The face was a tad misleading to me, the other reason for the half star loss. Yes kinda well on the blackness. In fact it is absolute like the depths of space. Just me rambling from the past numberous trips I have been privy to venture on. Shoot me a line if you need more direction on this... might would part with a pic or two for artistic purposes.