Hey, I'm as irrational as the next guy but come on. Molycorp just passed a $6 billion market cap on a 7 8% up-move.
Here's Avalon's daily chart via Wall Street Pit:

Why are things popping?
One of Molycorp's underwriters raised their price target:
Dahlman Rose Increases Molycorp PT To $125, Reiterates Buy