In the Animal Kingdom we know that Flamingos are pink from what they eat. They start out grey. And then after a diet of brine shrimp and blue-green algae, Pink! Other animals rely on Melanin. That gives colors tending to brown or reddish yellow.
But what about blue jays or poison dart frogs? The color blue is special. Like magic, it’s a trick of the light.
I’m thinking Violet Beauregarde (Willy Wonka) would have rather turned blue with a trick of light.