Some time ago I visited the mineral exhibition at the museum „Welt der Kristalle“ near Rottweil. Besides a lot of really fascinating crystals and minerals and some nice fossils was a really bizarre object on exhibit, a ram skull fully overgrown with fine selenite crystals.
This skull comes from Queensland, Australia.
It´s obviously not a very old skull, and the crystals must have grown within a time of no more than some decades.
.