Why are rubies red and emeralds green? Their colors come from the same metal in their atomic structure
- Written by Daniel Freedman, Dean of the College of Science, Technology, Engineering, Mathematics & Management, University of Wisconsin-Stout

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?
I am an inorganic chemist. Researchers in my field...