63. Europium: The Age Of Enlightenment

As element collectors, may we all one day be as fortunate as Frank Harold Spedding.

Featured above: Those beautiful red phosphors, close up.

Show Notes

Technology Connections is a YouTube channel hosted by a guy who knows a whole lot about electronics. I find his videos sort of quietly charming and highly informative. If you’d like to know more about the history and workings of televisions, he has a playlist totaling about 90 minutes that goes way in-depth on everything from the mechanical television to copy protection in VHS. I’ll embed it below:

h/t to Josh Crowley for letting me know about this channel!

As for the office machine that was the predecessor of the television? That would be none other than… the fax machine. You heard that correctly. The fax machine is nearly two centuries old, so actually, all that time spent banging my fist on the office fax while trying to file insurance claims makes a lot more sense.

Alexander Bain, a Scot, invented the first one in 1846. The idea behind it was that if you could synchronize a scanning device with a drawing device, you could send an image across vast distances. It was the bit about the drawing device that provided some inspiration for the television.

If that whets your appetite to learn more, the playlist above will be your cup of tea!

Episode Script

At the turn of the 20th century, Europe was absolutely humming with exciting activity. For the first time in history, many people spent their lives toiling somewhere other than a farm. Impressionism and Art Nouveau were shattering people’s ideas of what “art” could be. Scientists, meanwhile, were talking about a new and mysterious invisible phenomenon that sounded like witchcraft, which they called “radioactivity.” Bayer started selling a new, completely non-addictive painkiller called “aspirin.”1 2 3 4

The geopolitical situation was similarly novel. For centuries, the countries we know as Germany and Italy were much more fragments. The citizens were much more likely to affiliate themselves with the nearest city, like Florence, or Hamburg. That changed in the latter half of the 19th century. Otto von Bismarck spent his entire life making cunning political moves that culminated in the unification of Germany as a single country with a shared identity. Similar changes happened in Italy. The Appenine Peninsula hadn’t exhibited such togetherness since the days of the Roman empire.

Optimism was in full bloom, but so too had the seeds of conflict been sown. The citizens of these new nation-states were very proud people. They didn’t merely think highly of themselves, but groups of “others,” like Jews and the Romani, were unjustly vilified and cast out from these new societies — not that they had ever had it easy to begin with. Nationalism was on the rise, and set the stage for the next century of global conflict.5

This movement did not leave the sciences entirely unscathed. We’ve already learned about several different elements that earned their names in a bout of patriotic fervor.

So it’s a little encouraging to learn that, in 1901, when Eugene Anatole deMarcay [yoo-szhen en-ah-tole de-mar-say] became the first chemist to successfully isolate element 63, he named it not for the glory of his native France, but in honor of the entire continent: europium.6[/note] 7 8

Europium is slightly different from the rest of its lanthanide siblings. It’s the most reactive element in the series. It quickly oxidizes in the atmosphere, and with the slightest little nudge, it can emit a brilliant red light.9

It’s all rather fitting, since its namesake continent would soon be lit up with artillery fire due to unstable political conditions. And curiously enough, europium also plays a part in one of the most optimistic European ventures in modern history, too.

So let’s crack open those old history books, because if any episode deserves to be so flagrantly eurocentric, this is the one.

You’re listening to The Episodic Table Of Elements, and I’m T. R. Appleton. Each episode, we take a look at the fascinating true stories behind one element on the periodic table.

Today, we’re plopping down on the couch in front of europium.

Unlike most of the other rare earth elements, europium actually is relatively rare. On top of that, it’s also very difficult to isolate, which is why this was one of the last lanthanides to be discovered.10

Even so, it would still be several decades before element 63 was ready for prime time.


We talk about televisions a lot on this program, which isn’t too surprising. In a sense, the TV is one wildly popular and rather elaborate chemistry experiment.

Actually, the first televisions, built in the 1860s, were entirely mechanical. A disc lined with tiny holes, slightly offset from each other would spin extremely fast. As they whirred past an illuminated square, they would reveal a tiny image line by line, exploiting persistence of vision to give the illusion of motion.

It was quite clever, but not very practical. The spinning disc made a tremendous noise, and the entire apparatus would have to be several stories tall just to display the equivalent of a meager ten-inch screen. It was eventually surpassed by the classic cathode ray tube.

Those consist of a large, deep vacuum chamber made of thick leaded glass. (If you ever owned one, you’ll remember that the chief defining characteristic of these suckers is that they were heavy.) Without an atmosphere to interfere, electrons fired from the rear of the chamber can freely travel to the front of the display, where they strike a special coating and cause a tiny region of the screen to light up. The electron gun sends a constant beam sweeping across the screen, line by line, thousands of times per second.

A black-and-white TV is fairly simple. Varying the brightness as the beam travels across each line creates a spectrum of greys. A color television actually uses separate electron beams to draw three separate pictures on the screen: one red, one green, and one blue.

It’s considerably more complex to pull off this feat, for a number of reasons. Even as engineers refined the mechanism at work, early color televisions were less than impressive. They technically showed a color image, but it was a washed-out image, and those colors were muted.

The problem was with the phosphors coating the back of the screen. Those responsible for the green and blue portion of the image were just fine, but the red phosphors were disappointingly weak. The green and blue channels had to be toned down just to match the feeble red signal and maintain the overall color balance of the picture.

That changed in the 1960s when engineers found that phosphors based on europium are able to produce rich and bright red hues. This made for full, vibrant colors, as well as an image that was generally much brighter.

Television technology has left the electron gun in the past, but europium is just as critical in flatscreen displays as it ever was in CRTs. And europium’s luminous uses extend well beyond the squawk box.11

It’s actually a behavior that can be found in nature. When some samples of the mineral fluorite are exposed to ultraviolet light, which is invisible, the rock will in turn become suffused with an otherworldly blue glow.

The phenomenon was called “fluorescence” after that mineral, but it’s actually small amounts of europium that are responsible for the effect. It’s the same kind of shenanigans we’ve seen in a handful of other elements, like the noble gases: atoms of europium absorb a small amount of energy, causing one of its electrons to jump to a higher energy state. When the electron falls back down to its lower energy state, it releases the excess energy as light.12

This makes europium useful in the creation of various luminescent paints, dyes, pigments, and colors. But of all the fluorescent relics you could choose to represent element 63, the most appropriate one for my money is, well, money.

For as common as europium-based luminescent inks are, “common” is a relative term. You can’t exactly purchase europium cartridges for your inkjet printer.

That’s why it makes a good anti-counterfeiting technology. As difficult as it is to acquire, it’s very easy to verify its presence — simply use a UV light and watch it glow.

If you haven’t already guessed which currency employs this anti-counterfeiting technology, you’ll just about kick yourself when you hear. It’s not a trick — it really is the most obvious one. The answer, of course, is the euro.

We’re not often so lucky as to get such a thematically resonant piece for our collections. Unfortunately, in June 2020, intercontinental travel is somewhat inconvenient on account of the pandemic. If you don’t exchange euro notes on a regular basis, you probably won’t get a chance for quite some time.

Nor are you likely, I’m afraid, to get as lucky as Frank Harold Spedding. He was a chemist who had spent his early career studying crystal symmetry, and at the 1933 World’s Fair in Chicago he was awarded the prestigious Langmuir Prize for that work.

After giving his acceptance speech, he walked offstage and was approached by a total stranger, a bookish older gentleman with powder-white hair. Apropos of nothing, he said, “How would you like to have a pound of europium and two or three pounds of samarium?”13

This offer truly was as bizarre as it sounds — even more odd than if a stranger made the same offer to you today. In 1933, both of those elements were exceedingly rare, and it was pretty expensive just to obtain a few milligrams of either.

Spedding very cautiously agreed, mostly in the hopes that this fellow would move along. He did, much to Spedding’s relief, and the entire incident would’ve been quickly forgotten but for one thing: A few weeks later, a box full of fruit jars was delivered to his doorstep, each containing substantial amounts of the promised elements. They were  quite valuable in the right hands, and did turn out to be quite useful in Spedding’s ongoing research.14

The attached letter revealed that his mysterious benefactor was none other than Herbert N. McCoy, a renowned professor of chemistry at the University of Chicago. He had performed his own experiments in crystallography, supplying him with vast reserves of rare earth elements, and he realized he was uniquely positioned to help other scientists.15 16

So, you could hang around your local convention center and hope you’ll win the weirdest lottery on Earth, but personally, I wouldn’t recommend it.

Luckily, there is another quite practical option, regardless of your proximity to Prague, and without holding on to an old, broken, behemoth of a television set.

Europium’s ability to light up a room is on full display in compact fluorescent bulbs, the kind you may very well have installed in your lamps around the home. So the next time one of them flickers off for the last time, maybe you’ll consider holding on to it. Even though it sheds light no longer, it can still do a perfectly good job brightening your shelf of the elements.17

Thanks for listening to The Episodic Table of Elements. Music is by Kai Engel. To learn what office technology is a direct ancestor of the television, visit episodic table dot com slash E u.

The fifteenth annual People’s Choice Podcast Awards will soon be open for audience nominations. If you enjoy the program, your vote would mean more than you might think. If you’re listening to this on or after July 1, you can visit episodic table dot com to see how you can participate.

Next time, we’ll study an element that sheds no colors at all with gadolinium.

Until then, this is T. R. Appleton, reminding you that it’s extremely hazardous and inadvisable to poke your fingers around the high-voltage interior of a cathode ray tube.

Sources

  1. The Met Museum, Central Europe, 1900 A.D.-Present.
  2. Comptes Rendus Physique, The Discovery Of Radioactivity. Pierre Radvanyi and Jacques Villain, November/December 2017.
  3. Science History Institute, Felix Hoffman. Last updated December 8, 2017.
  4. The British Library, Europe Before 1914. David Stevenson, January 29, 2014.
  5. Encyclopedia Britannica, Nationalism. Hans Kohn, last updated February 19, 2020.
  6. The Chemical News, On The Phosphorescent Spectra Of Sa[?] And Europium. William Crookes, July 21, 1905.
  7. World Of Chemicals, Eugene-Anatole Demarcay — Discoverer Of Europium Element.
  8. Elementymology And Elements Multidict, Europium. Peter van der Krogt.
  9. The Periodic Table: A Field Guide To The Elements, this page. Paul Parsons and Gail Dixon, 2013.
  10. Encyclopedia.com, Europium. Jean-Claude Bunzli, 2006.
  11. The Periodic Table: A Visual Guide To The Elements, p. 179. Tom Jackson, 2020
  12. Encyclopedia Britannica, Luminescence Physics.
  13. Biographical Memoirs, p. 305. The National Academies Press, 2001.
  14. The Annals Of Iowa, p. 60-61. Joanne Abel Goldman, 2008.
  15. Biographical Memoirs, p. 305. National Academy Of Sciences, 2002.
  16. Extractive Metallurgy Of Rare Earths, p. 82. Nagaiyar Krishnamurthy and Chiranjib Kumar Gupta, 2015.
  17. DownToEarth, Unpacking Europium, The Mainstay Of The Lighting Industry. Venkat Srinivasan, September 17, 2015.

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