While some people may appear to have irises that are black, they don't technically exist. People with black-colored eyes instead have very dark brown eyes that are almost indistinguishable from the pupil.
Black Eyes.
There's an eye disorder known as aniridia which makes the eye appear to have “no iris.” In truth, there is a small ring of iris tissue, but it is so small and the pupil is so large that it can look like the eyes are completely black. It is due to a chromosome mutation.
Normal eye colors range from the darkest shades of brown to the lightest tints of blue.
Green is considered by some to be the actual rarest eye color in the world, though others would say it's been dethroned by red, violet, and grey eyes. Green eyes don't possess a lot of melanin, which creates a Rayleigh scattering effect: Light gets reflected and scattered by the eyes instead of absorbed by pigment.
Brown eyes
Brown is the least rare of eye colours and can range from dark chocolate hues to lighter chestnut shades. They can sometimes appear black as they tend to blend with the pupil of the eye; however, this is an illusion as black irises don't exist.
Did Elizabeth Taylor have violet eyes? These days, thanks to colored contact lenses, anyone can have violet-colored eyes . Taylor didn't come by her purple peepers that way; the first tinted contact lenses weren't commercially available until 1983. Taylor's eye color was the real deal.
We found that green is the most popular lens colour, with brown coming in a close second, despite it being one of the most common eye colours. Although blue and hazel are seen as the most attractive eye colours for men and women they are surprisingly the least popular.
Rarest Eye Colour – Green.
Unbelievable as it may seem, the answer is yes—natural purple eyes do exist. Purple eyes are also commonly referred to as “violet eyes,” as they are typically a light shade. For most people, this striking eye color can only be achieved with the help of colored contacts.
True purple eyes are exceedingly rare. Less than 1% of the world's population has them, making them rarer than blue, hazel, amber, grey, or green.
Blue is the second most common eye color globally, with an estimated 8 to 10 % of people having blue eyes. A majority of these people are of European descent, however, Black people can be born with blue eyes even though it's pretty rare.
Brown eyes may have ranked as the least attractive, but they were 1.6 times more likely than blue eyes to be described as trustworthy.
Black is not an eye color. While some eyes may look black, they're either just a very dark brown or have large pupils (more on this below).
Black Eyes
Have you ever seen someone with eyes that seem black as night? Although they appear black, they are really just a very, very dark brown, which is caused by an abundance of melanin. You may only be able to determine the pupil from the iris when looking at the eye with a bright light!
Red eyes are caused by a group of diseases called albinism. There are several kinds of albinism, and each affects the body somewhat differently. Generally, they are disorders that are inherited genetically which involve hypopigmentation of the parts of the body like the hair, skin or eyes.
Most black eyes are no more dangerous than a simple bruise on your arm or leg. There are times, however, when a black eye can be a sign of a more serious problem, such as a fracture of the eye socket or an injury to the inside of the eye.
The whites of your eyes (called the sclera) turn yellow when you have a condition called jaundice. The whites of your eyes might turn yellow when your body has too much of a chemical called bilirubin, a yellow substance that forms when red blood cells break down.
Though common in some breeds of cats, dogs, cattle and horses due to inbreeding, heterochromia is uncommon in humans, affecting fewer than 200,000 people in the United States, and is not associated with lack of genetic diversity.
Amber eyes are extremely rare. Most sources say that only about 5% of people have true amber eyes. Coming up with a hard and fast number or percentage, though, is not as easy as you might think—there simply haven't been enough large-scale studies done to quantify eye color prevalence with certainty.
Eye Color Changes Not Related to the Iris
Arcus senilis is a hazy blue or white ring on the cornea from a build-up of a natural fatty substance called lipids. It's common with aging and usually harmless. Most seniors have some degree of arcus senilis.
The rarest skin color in the world is believed to be the white from albinism, a genetic mutation that causes a lack of melanin production in the human body. Albinism affects 1 in every 3,000 to 20,000 people. What is this? People with albinism usually have very pale or colorless skin, hair, and eyes.
The iris has pigmentation that determines the eye color. Irises are classified as being one of six colors: amber, blue, brown, gray, green, hazel, or red. Often confused with hazel eyes, amber eyes tend to be a solid golden or copper color without flecks of blue or green typical of hazel eyes.
Scientists at the University of Louisville, Kentucky, have apparently found a hitherto unobserved link between eye-colour and levels of intelligence. Blue-eyed people, they claim, are more studious, more strategic, more focused, and thus out-perform brown-eyed people in exams.
Permanent changes to eye color can be achieved through iris implant surgery, corneal pigmentation, and laser eye color change. Iris Implant Surgery is a procedure that inserts a prosthetic iris into the eye. It was originally developed to treat iris defects such as albinism and aniridia.