Hazel eyes are due to a combination of a Rayleigh scattering and a moderate amount of melanin in the iris' anterior border layer. A number of studies using three-point scales have assigned "hazel" to be the medium-color between brown and dark brown. This can sometimes produce a multicolored iris, i.e., an eye that is brown near the pupil and charcoal or amber on the outer part of the iris when it is open to the elements of the sun/shined in the sunlight. Hazel is mostly found in the regions of South and East European nations and Britain.
Some eye colors are too mixed to identify properly, and are simply called hazel for simplicity's sake. This eye is dark gray with orange toward the center and blueish green towards the edge.
Some eye colors are too mixed to identify properly, and are simply called hazel for simplicity's sake. [...]
There is some difficulty in defining the eye color "hazel" as it is sometimes considered to be synonymous with brown and other times with green. They have been described as light brown or yellowish brown, or as a lighter shade of brown. Hazel eyes have also been described as being equivalent to a dark black or charcoal-colored/light black eyes. In North America, "hazel" is often used to describe eyes that change color, ranging from light brown to green and even blue, depending on what color clothing the person is wearing or what color is predominant in their immediate environment.
Und dieses schöne deutsche Volkslied darf natürlich nicht fehlen:
"Schwarzbraun ist die Haselnuss,
schwarzbraun bin auch ich,
schwarzbraun muss mein Mädel sein,
gerade so wie ich."