There are three main forms, each offering a fascinating variation in color. Complete heterochromia: Each eye has a completely different color. Imagine a green eye and a hazel eye, or a blue eye ...

The team, who experimented on themselves and others, hope their findings could one day help improve tools for studying color ...

A team of scientists in California say they have discovered a new color they named olo, but you can't see the "most intense teal" with the naked eye.

Scientists have created a technology called Oz that stimulates individual photoreceptor cells in the human eye to create an entirely new, ultra-saturated color never seen in nature—dubbed olo.