India, Feb. 16 -- Chemistry and physics are all very well, but the future of paint could well be geometric. And our guides in this field, are butterflies.

The lessons aren't coming from their powdery pigments, but from their iridescence, which is the result of an intricate network of scales on their wings.

These scales have no inherent colour. They are, instead, layered and separated by pockets of air. This scatters and diffracts light, often several times across the tiny span, causing the flashes of vivid colour we see as certain butterflies flit past.

After decades of trying, scientists were finally able to replicate this effect in a lab, in 2023.

"The entire structural colour community has been working on this for many years," says...