I think you forgot to respond to me about tyrosine in all that mess.
Also, in fact neither you nor Guy are right about real-life copper based blood, because we
have animals with copper-based blood on Earth; there are invertebrates with hemocyanin here on Earth, a heme molecule that is in fact based on copper, not iron, and their blood is
blue. And not greenish-blue even, but very specifically blue, as you can see
here and
here. Vulcans in Star Trek having copper-based blood was due to the same misunderstanding of biochemistry as that. (Guy's closer, but copper toxicity leaving brown rashes has nothing to do with blood. The copper buildup that causes copper toxicity doesn't bind with hemoglobin, it's free in the blood stream. I believe the rashes are because of free copper migrating into the skin, similar to argyria with silver; you're literally seeing the inorganic copper deposits themselves.)
You're right that
copper oxide is green and
iron oxide is red, jmidnight, but neither of those has anything to do with heme molecules, because those are far more complicated than just oxidizing metal ions. There is no iron oxide in your blood except what might be absorbed dietarily. It's essentially nothing more than a coincidence that iron oxide and hemoglobin are both red, and the fact that the color of blood isn't actually anywhere near the actual color of rust should be suggestive of that. Plus the fact that blood is red whether or not it's oxidized.
If anything, green blood should probably involve
sulfur in some way, not copper, given sulfhemoglobinemia. Though that might also be overly reliant on the traits of our specific blood.