Okay, here's a question...

[vr_trakowski]

Human blood uses iron to transport oxygen molecules.  Oxygen-carrying blood is red--it's oxidized, after a fashion...rusty.  Fine. 

Vulcan blood (I know, work with me here) uses copper to transport oxygen.  Oxygenated copper turns green (or greeny-blue).  So... 

Is unoxygenated Vulcan blood...red?