Like most websites The Ophthalmologist uses cookies. In order to deliver a personalized, responsive service and to improve the site, we remember and store information about how you use it. Learn more.
Subscribe to Newsletter
Subspecialties Comprehensive

Journey into the Blue

Science journalist and molecular biomedicine specialist Kai Kupferschmidt has an unusual fascination: the color blue. For him, the color holds many mysteries – especially in living nature, where it is among the rarest of hues. To find out more, Kupferschmidt dove deep “into the blue,” unearthing its most unusual presentations – including those in chemistry, biology, and beyond – and published them in the book Blue: In Search of Nature’s Rarest Color.

What was the most interesting fact you encountered while researching the book?

There are so many! I think what most fascinates me are the connections that become apparent between things that seem so unrelated. One example: alchemists accidentally discovered a new blue pigment named “Prussian blue” in the early 18th century. It quickly spread around the world and was used in many masterpieces (for instance, Van Gogh’s Starry Night, Hokusai’s Great Wave Off Kanagawa, and Picasso’s blue period). But scientists investigating the chemical structure of this pigment derived a new compound called prussic acid – hydrogen cyanide – the eventual basis of the Zyklon B used in German extermination camps.

At the same time, Prussian blue itself is today recognized as an essential medicine that can be used to treat radioactive cesium poisoning.

I’ve always been fascinated by the poison tetrodotoxin and knew all about the pufferfish and how it is prized as a delicacy in Japan. But there is another deadly animal called the blue-ringed octopus that uses the same toxin. To warn its enemies, it can make the blue rings on its skin pulsate. It’s beautiful and terrifying; if I wrote mystery novels, I would definitely include it in my next book.

Another of my favorite stories is about the blue of the cornflower. In 1913, Richard Willstätter isolated the molecule at the heart of it and called it “cyanidin.” Two years later, he isolated the red of red roses and it turned out to be the same molecule. Today, we know that the cornflower does a lot of crazy chemistry to appear blue; it actually combines six molecules of cyanidin with six co-pigments and arranges the whole thing around metal ions like spokes on a wheel. And we really only got final confirmation of this with X-ray crystallography done in 2005!

How do you want the reader to feel as they are reading Blue – or when they’ve read the final page?

I hope that they will take a sense of joy and wonder from it – and, more than anything, a sense of curiosity about the world. We all get so used to the beauty and improbability of all that is around us. Writing the book and understanding what is involved in all those blues we see certainly made me look at the world with different eyes. I really hope readers will have the same experience.

The sections – Stones, Seeing, Plants, Speaking, Animals – guide readers through Blue. But what were the main challenges in pulling together a book on a single color from so many different angles?

Blue is such a huge subject that I really had to let go of the desire to cover everything. And that was really hard in the beginning but, at some point, I learned to simply follow my curiosity. The book is just one path through a huge garden filled with stories and knowledge about blue. The simple, clear structure I adopted helped ensure that, even though I was wandering, I would never get entirely lost.

Which concepts within Blue’s pages are most likely to fascinate our readers?

The question of the sense in which a color like blue actually exists is mesmerising. We can measure so much about our eyes and our vision, but there is ultimately a mystery at the heart of our perception; that sense of “blue” I perceive is inside me and I cannot know if you experience it in the same way. As philosopher Ludwig Wittgenstein wrote: “Look at the blue of the sky and say to yourself ‘How blue the sky is!’ When you do it spontaneously – without philosophical intentions – the idea never crosses your mind that this impression of color belongs only to you.”

Why do you think blue is the world’s favorite color?

I think it has a lot to do with the associations we have. The clear blue sky, the vast ocean – there is something beautiful and relaxing about these large masses of blue and, at the same time, you cannot really touch them or take them home. In living nature, blues are rare, and that may make us like it even more.

What’s your favorite shade of blue – and why?

When I was researching this book, two blues in particular struck me. One was Yves Klein’s International Klein Blue. I traveled to Paris to see one of his works in real life and it is magnificent. The synthetic ultramarine he used with a very specific binder really packs a punch. Photos don’t do it justice. The other blue was YInMn blue, a new blue pigment that I got to make myself in the lab of the researcher who discovered it, Mas Subramanian. There was something magical about the way these three bland powders, mixed together and heated in an oven, produced this brilliant blue.

Any plans for the natural follow ups – Red and Green?

No. “Blue” was a real journey for me and, as it turned out, a very personal one. I think I will leave “red” or “green” to someone else who will have their own journey tied to that particular color.

Is your journey into “blue” complete?

Right now, it feels complete. But, at the same time, there are so many more paths to take in that garden – and the garden keeps growing and changing. I will keep exploring anything “blue” because it is my passion and maybe, one day, I will feel like charting another course through that garden. Who knows?

Finally, how can readers join you on your “globe-trotting quest” to find blue in the natural world?

Excellent question! “Blue: In Search of Nature’s Rarest Color” can now be purchased online.  

Receive content, products, events as well as relevant industry updates from The Ophthalmologist and its sponsors.

When you click “Subscribe” we will email you a link, which you must click to verify the email address above and activate your subscription. If you do not receive this email, please contact us at [email protected].
If you wish to unsubscribe, you can update your preferences at any point.

About the Author
Rich Whitworth

Content Director at Texere Publishing.

Register to The Ophthalmologist

Register to access our FREE online portfolio, request the magazine in print and manage your preferences.

You will benefit from:
  • Unlimited access to ALL articles
  • News, interviews & opinions from leading industry experts
  • Receive print (and PDF) copies of The Ophthalmologist magazine