I learned something new about my friend Elbert when he was visiting recently. His second- and third-favorite colors are white and "chocolate," respectively. So he's already out there on the margins of the color wheel. But his favorite color of all, he insists, is clear.
"That's not allowed. Clear isn't a color."
"Yes, it is."
So, that's that. Why Crayola doesn't issue a crayon in its jumbo pack that contains no dye and just makes the paper all shiny, I don't know.