copper broke down rather dramatically a couple weeks back, but...
mining stocks did not. companies like FCX or NEM held up even as copper broke down.
this may be a rather strange non-confirmation.
i would expect the mining stocks to break down before the metal. or at least at the same time.
Copper-3 month chart below
Copper chart 1 year below
Copper Chart 5 years below
Copper Chart 10 years below