Its poop.
some guy who was really into area 51 crap gave it to my dad 15 years ago and ive had it ever since. although it doesn't respond to magnets and its not heavy, its covered in regmaglypts which are basically lots of small indentations. its covered in a smooth black hard surface which looks like fusion crust. it also has a bunch of orange dots covering it which may be rust or mineral mud. plus it isnt porous like volcanic rock
Not sure if bot...