Heterochromia iridum is the formal name for when a person’s irises are multi-colored, often with streaks or swirls of one color cutting through another. In this short film, photographer Rus Khasanov recreates the effect with glittery inks and paints. Their varying surface tensions help create the eye-like streaks and feathers through the Marangoni effect. Check out the full video to see the effect in action. (Image and video credit: R. Khasanov; via Colossal)