Lined and hardened, as though by exposure and want of personal care, there was also a lack of sensibility, an almost animal callousness, on the coldly lit eyes and unflinching mouth, which readily suggested some terrible and recent experience--something potent enough to have dried up the human nature out of the man and left him soulless.
Eye colors depend on the amount of pigment (melanin) found in the iris and how it is distributed. Light gray-blue eyes contain much less pigment than extremely dark brown eyes. And there are many shades of eye color in between.
Eye color can also change depending on the light. For example hazel eyes may look different in indoor and outdoor light. Since hazel eyes often change color, people with hazel eyes are said to be unpredictable and fun loving. This is a common stereotype associated with this eye color. Green eyes are said to be mischievous and since hazel eyes can have elements of green, they also carry this stereotype.