@Felthry You can trademark a color by claiming that your brand is distinguished by it. Coca Cola's red, McDonald's yellow, UPS's brown, Tiffany's blue - all of these are trademarked.
@Tathar @Felthry You think wrongly. https://en.wikipedia.org/wiki/Colour_trade_mark#United_States
Oh, this is why I thought that. https://tmep.uspto.gov/RDMS/TMEP/current#/current/TMEP-1200d1e1975.html