The Most Rare Colored Fruit
The tiny, rock-hard fruits of Pollia condensata, a wild plant that grows in the forests of several African countries, can’t be eaten. But they have an extremely rare property for a plant. They stay vibrant, metallic blue for many decades, even after they’ve been picked. They produce the most intense color ever studied in biological tissue.
The vast majority of colors in the biological world are produced by pigments—compounds produced by a living organism that selectively absorb certain wavelengths of light, so that they appear to be the color of whichever wavelengths they reflect.
However, Pollia condensata produces its vibrant blue color through nanoscale-sized cellulose strands that scatter light as they interact with one another. Thus the fruit’s color is visible at the cellular level as pictured above.