Compact Curiosities: TV Rock

Hydrated sodium calcium borate hydroxide (Ulexite to its friends, TV Rock to its pals) is a structurally complex mineral that formed masses of parallel mineral fibers, like a naturally occurring fiber optic mass.

You can place it on any surface and see a "broadcast" of what's below through the rock. 

Not recommended in conjunction with flame or steam powers, as Ulexite can dissolve in hot water.