The colors of rubies and emeralds are so striking that they define shades of red and green – ruby red and emerald green. But have you ever wondered how they get those colors? One feature of compounds ...

What does "reddish green" look like? Not brown, not olive - an actual color that's simultaneously red and green the way cyan ...

Daniel Freedman does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond ...