The blue butterfly that isn’t really blue

2 min readSep 21, 2021

One of the most famous Amazonian species is the blue morpho butterfly.

Blue Morpho Butterfly

It is remarkable not only for its size (with a wing span of up to 20 centimetres) but also its eye-catching colour. It’s so bright it looks like someone has altered it in Photoshop.

The strange thing is, it’s wings aren’t actually blue. In fact, they have no colouring at all.

How can this be?

Viewed under a microscope, a blue morpho butterfly’s wings are made up of diamond-shaped scales. Their formation reflects the light in such a way that they appear to be a brilliant blue. This type of visual illusion is known as iridescence.

The research team at Lexus in Japan were intrigued by this eye-catching phenomenon and wondered if a similar technique could be used to colour their cars.

In collaboration with material scientists and a specialist paint company, they figured out how a similar iridescent effect could be applied to vehicle paint.

The end result was the Lexus LC Structural Blue Edition.

Offered in limited numbers at around $100,000, the car has a mesmerising finish that appears blue and yet doesn’t contain any blue pigment.

Lexus claims that while normal automotive blue paint reflects less than 50 percent of incoming light as blue, Structural Blue reflects almost 100 percent.

As blue as blue paint can ever be!

The Lexus LC Structural Blue Edition

Structural colour could have many applications beyond automotive paint.

Consider the fashion industry as one example. It receives justifiable criticism for the toxic dyes used to colour clothing.

Structural colour could offer a sustainable alternative.

If you found this post interesting, then you will enjoy our upcoming course on Biomimicry which dives deeper into the study of how nature can help us to innovate.

Find out how Velcro, barbed wire and many other popular products used nature’s secrets in their design.




Learn about life the universe and everything from a bunch of people at a fun edtech company.