@Chet31: If someone were to give you a ride in their car, and while driving they were to casually pull out an armed nuclear explosive capable of killing you and everyone for hundreds of miles around you, and then they were to casually toss it to themselves and juggle it with one hand, paying no attention to it, even though it was set with an impact trigger that would set it off the instant he dropped it, do you think perhaps that maybe you would freak out a little bit?
The singing crystal is an incredibly illegal weapon of mass destruction. It could annihilate all life on a planet, and even completely wipe out a civilization if said civilization lacks a strong military force to oppose it. Mere possession of it could get the whole crew sent to prison, and that's if they're lucky.