Saw this on facebook and have to say, um, no.
There’s no indication whatsoever in the Hebrew text that Cain killed Abel with a rock. David killed Goliath with one (or more precisely, knocked him cold with one and then hacked his head off with his own sword). But the Bible doesn’t say how Abel was killed (though strangulation is a possibility, given the verbs used in the story).
This is some more facebook theology that makes me sigh.