This is the most beautiful scientific diagram I've ever seen.
Also a great example of why pink is a tint of red, but also a completely different color. Erbium? Neodymium? So beautiful.
Manganese was one of the additives originally included to produce clear glass by neutralizing the greenish color cause by (cheap) iron rich sands! It was obviously later discovered that it turns purple (amethyst) with extended exposure to sunlight. It's also called solarized glass.
Lockhart, Bill. 2006b. The Color Purple: Dating Solarized Amethyst Container Glass. Historical Archaeology 40(2):45-56. https://secure-sha.org/bottle/pdffiles/TheColorPurpleLockhart2006.pdf
(for extra historic bottle info https://secure-sha.org/bottle/index.htm )



















