You see, the color of the iris is determined primarily by the concentration and distribution of melanin, for example, brown eyes have large amounts of melanin pigment deposits, and blue eyes have a lack of melanin. Heterochromia iridis is a condition in which the iris in one eye has a different color than the iris of the other eye. The affected eye may be hyperpigmented (hyperchromic) or hypopigmented (hypochromic). In other words, an excess of melanin or the lack of it changes the color of the iris. But this photo presents an even rarer condition, when areas of the same iris are different in color, known as 'segmental or sectoral heterochromia'. Sectoral Heterochromia looks like an irregular spot that is a different color than the eye color and does not form a complete ring around the pupil. Most cases of heterochromia iridis are not associated with any symptoms or problems.