Why The Hatter has orange hair?
I think it was just an aesthetic choice. He wanted a bright color, no doubt, and red is the brightest color human hair. Also, red hair has a bit of a reputation in British culture. Exactly what is hard to put, but being emotional and fighting are often considered red head traits. It is also plausible, but a bit of a stretch, to connect the orange red hair with Cinnibar. Cinnibar is the mineral ore from which mercury is extracted. Mercury, in turn, was used in felt hat making and poisoned the workers until it was banned. The phrase “mad as a hatter” may have come from this occupational disease. The phrase was around long before Carrol used the notion in Alice; but, we know about the connection between mercury and madness in hattes now so the movie folks could have made the connection with the orange mineral.
