What is the color of Mr. Spock's blood?

Answer 1

green

Answer 2

Vulcan blood is green, however Mr. Spock is only half Vulcan. True, he is always referred to as being green blooded, yet watch carefully during the episode "The Man Trap."
     In this episode, Spock sustains a cut on his forehead, and although it is surrounded by blood of a greenish hue, the cut itself appears to be red. This could either be an simple error within the episode, or perhaps an allusion to the concept of his blood being both Human and Vulcan; Green AND red.