Editing Eye color (section)

===Gray===
[[File:Gray eye, Northern Italy.jpg|thumb|Gray eye]]
Like blue eyes, gray eyes have a dark epithelium at the back of the iris and a relatively clear stroma at the front. One possible explanation for the difference in appearance between gray and blue eyes is that gray eyes have larger deposits of [[collagen]] in the stroma, so that the light that is reflected from the epithelium undergoes [[Mie scattering]] (which is not strongly frequency-dependent) rather than Rayleigh scattering (in which shorter wavelengths of light are scattered more). This would be analogous to the change in the color of the sky, from the blue given by the Rayleigh scattering of sunlight by small gas molecules when the sky is clear, to the gray caused by Mie scattering of large water droplets when the sky is cloudy.<ref name="Southworth">{{cite web |url=http://www.thetech.org/genetics/ask.php?id=232 |title=Are gray eyes the same as blue in terms of genetics? |work=Understanding Genetics: Human Health and the Genome |publisher=Stanford School of Medicine |author=Lucy Southworth |access-date=19 October 2011 |archive-url=https://web.archive.org/web/20110927085904/http://www.thetech.org/genetics/ask.php?id=232 |archive-date=27 September 2011 }}</ref> Alternatively, it has been suggested that gray and blue eyes might differ in the concentration of melanin at the front of the stroma.<ref name="Southworth" />

Gray eyes can also be found among the [[Algeria]]n [[Shawia people]]<ref>{{in lang|fr}}  [https://books.google.com/books?id=7rwBAAAAYAAJ&pg=PA272 Provincia: bulletin trimestriel de la Société de Statistique ...], Volumes 16–17 By Société de statistique, d'histoire et d'archéologie de Marseille et de Provence p. 273 ''l'iris gris est celui des chaouias...''</ref> of the [[Aurès Mountains]] in Northwest Africa, in the [[Middle East]]/[[West Asia]], [[Central Asia]], and [[South Asia]]. In the ''[[Iliad]]'', the Greek goddess [[Athene]] is said to have gray eyes (γλαυκῶπις).<ref>''[[Iliad]]'' 1:206 http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.01.0133%3Abook%3D1%3Acard%3D206</ref> Under magnification, gray eyes exhibit small amounts of yellow and brown color in the iris.

Gray is the second-rarest natural eye color after green, with 3% of the world's population having it.<ref>{{Cite web|title=Gray eyes|url=https://www.allaboutvision.com/eye-care/eye-anatomy/gray-eyes/|access-date=2021-05-09|website=All About Vision|language=en-us}}</ref>