Nothing. Because rocks don't talk and geology's not funny.
What do you mean what do I mean?" replied the man. He went on to explain "My son has half my genes, that makes him my half-son." The woman he was talking to decided he was crazy and without replying walked past him. She looked back and noticed his neck was red, after all it was a sunny day.
Guess I can't see what everyone else sees.
You hit rock bottom!
With one he turns off the light, With the other he checks if the window is closed
Rock concerts.*
His boss always took him for granite.
Robin Williams