Well I'll tell you then. ****ing raw Osmium, Wolfram/Tungsten, titanium and Iridium. My science officer has been studying the digestive system. And everything except those elements seem to flush right through. It seems to mainly get it by swallowing mineral rich asteroids whole. And needless to say, **** out the excess rock. Definitely explains their overall toughness.
Seriously doubt this material can be used for anything. It's mass-density is about two thirds of a neutron star. So it'll be ****ing impossible to both extract, shape, transport etc.