True natural purple eyes are not a recognized human eye color. While eyes can appear to have violet or purplish hues under certain rare conditions, this is not due to a distinct purple pigment. Human eye colors arise from specific biological mechanisms.
The Mechanics of Eye Color
The color of human eyes primarily depends on the amount and type of melanin present in the iris, the colored part of the eye that surrounds the pupil. Melanin, a pigment also responsible for skin and hair color, is produced by specialized cells called melanocytes. The concentration and distribution of these melanin types within the iris largely determine the final eye color.
Brown eyes, the most common eye color globally, result from a high concentration of melanin. Conversely, blue eyes contain very little melanin in the front layers of the iris. Their blue appearance stems from Rayleigh scattering, where light is scattered by collagen fibers, causing shorter blue wavelengths to reflect. Green and hazel eyes have intermediate levels of melanin, creating a blend of colors through both pigmentation and light scattering effects. The genetic basis of eye color is complex, influenced by multiple genes that regulate melanin production and distribution.
When Eyes Appear Violet or Purple
Eyes can sometimes appear violet or purple, but this is an optical effect or a consequence of specific genetic conditions rather than the presence of purple pigment. The most notable instance is observed in some individuals with albinism, a genetic condition characterized by a reduced or complete absence of melanin in the body, including the eyes.
In oculocutaneous albinism, the severe lack of melanin in the iris allows light to reflect off the blood vessels at the back of the eye. This can result in a reddish or pinkish appearance, which under certain lighting conditions can combine with the scattered blue light from the iris to create a violet or lavender hue. Most individuals with albinism actually have blue, hazel, or brown eyes, with the reddish or violet appearance being less common and highly dependent on lighting.
Beyond albinism, the perception of eye color can also be influenced by external factors. Specific lighting conditions, such as low light or certain artificial lights, can alter how colors are perceived, making deep blue or gray eyes appear more violet. The colors of surrounding objects, clothing, or makeup can also create an illusion, enhancing the perceived purplish tint of the eyes.
Separating Fact from Fiction
The notion of naturally purple eyes is often fueled by popular culture and common misconceptions. A prominent example is the widespread belief that actress Elizabeth Taylor had natural violet eyes. While her eyes were a striking deep blue, their unique shade often appeared violet under specific lighting conditions, due to makeup, or in photographs. Her passport even listed her eye color as “dark blue,” reinforcing that her eye color was a deep blue that simply appeared purplish.
For individuals desiring purple eye color, colored contact lenses provide a cosmetic solution. These lenses are designed with opaque or translucent tints that cover the natural iris, allowing individuals to temporarily change their eye color to various shades, including purple. This accessibility to artificial eye color further contributes to the misconception that naturally occurring purple eyes are a biological possibility. True, naturally pigmented purple eyes are not a biological reality.