74. Tungsten: What Is The Atom We Love?

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All right, everybody settle down. Welcome to the weekly meeting of the National Association Of W Lovers.

 

Show Notes

More to come later, but for now:

Portugal was neutral during World War 2, which was a difficult position to maintain. They were afraid that Germany might invade, especially after the fall of Paris, or even that they might be subject to a proxy war via Spain.

Portugal also had a huge supply of tungsten, basically a monopoly, and the metal was in high demand at the time — for basically the same reason that molybdenum was during WWI. That made remaining neutral even harder than it already was, and Portugal wound up selling tungsten to both sides during the war — the Allies for the good money, and the Axis to try to keep the enemy at the gates, so to speak.

Portugal’s neutrality wound up playing a major role in the war. At the end of Casablanca, Laszlo and Ilsa go to Lisbon (spoilers). This was the case for plenty of people in real life, too. Lisbon was the last way in or out of Europe. Despite being ruled by an authoritarian (Antonio Salazar) who dealt with the Nazi government, Portugal nonetheless played a key role in helping the Allies.

Episode Script

The only people who don’t love Oliver Sacks are those who are not yet familiar with him. A neurologist, naturalist, historian, and modern-day polymath, Sacks became famous for writing nonfiction books about his most fascinating patients. The Island Of The Colorblind, An Anthropologist On Mars, and The Man Who Mistook His Wife For A Hat are but a few of his best-selling works. He treated his anonymous subjects not as bizarre curiosities or freakish aberrations, but first and foremost as humans who deserved respect and compassionate care. He was sort of a Sigmund Freud by way of Fred Rogers.

A knack for science seems to have run in the family. His grandfather worked with lamps in the 1870s; his mother was a surgeon who loved chemistry; among his nearly one hundred cousins were throngs of teachers, doctors, and mathematicians; and his Uncle Dave worked almost exclusively with element 74. One day, Uncle Dave pulled his nephew aside for a special demonstration: he filled a small bowl with mercury, the metal that’s so famously liquid at room temperature. He then dropped a lead bullet into the bowl. Despite the bullet’s considerable weight, mercury is more dense, so the bullet floated atop the metal’s surface. Intriguing — but there was one more thing. The part that Michael Caine might call “the prestige.”

He pulled out a little grey ingot of the metal he loved, his metal, with its unique feel and sound and weight. This, too, he dropped in the bowl of mercury… and it plunged straight to the bottom.

Young Oliver had great respect for this metal and even greater respect for his uncle.. Decades later, when Sacks was writing his childhood autobiography, he gave the book the same name he had for Dave: Uncle Tungsten.

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.¹

Today, we’re foaming at the mouth for tungsten.

Tungsten isn’t just a refractory metal — it’s the most refractory metal on Earth.² An alloy of tantalum, hafnium, and carbon has the highest melting point of anything we’ve discovered yet, and carbon actually has a higher melting point too, but among the pure elemental metals, tungsten can take the most heat before liquefying: roughly 3,400 degrees Celsius. For reference, liquid hot magma is usually around 1,000 degrees Celsius.

Strangely, for all that resilience, pure tungsten is soft enough to cut with a hacksaw. Don’t try it, though, because the smallest contamination is enough to make it almost as hard as diamond. Practically, this makes it very difficult to shape tungsten. When it needs to be worked into a particular shape, it’s often not melted at all, but sintered. Sintering is a process that applies high heat — lower than its melting point, but still pretty hot — and combines that with very high pressures to form a solid shape. It’s akin to picking up a handful of powdery snow and packing it into a tight snowball.³

All these tricks and traits are relatively recent discoveries. For centuries, tungsten was nothing more than bad news — especially for tin workers. When smelters worked with tin, if any tungsten-rich minerals polluted the mix, it had a tendency to “gobble up” the tin, like a wolf devours sheep, and ruin the batch. This is actually where one of the names of today’s element comes from. In 1556, our old pal Georgius Agricola described it as “wolf’s foam” — in German, wolf rahm. The troublesome mineral, then, was called wolframite.^{4 5}

You’re probably connecting the dots in your head already, so I’ll just go ahead and confirm your suspicions: That is why the symbol for today’s element is W. Okay, but then, wherefore the name tungsten?

Two hundred years later and across the Baltic Sea, Carl Wilhelm Scheele was analyzing a sample of the mineral known as scheelite. He was pretty sure there was a new element in that rock, and he suggested that the element take its name from the mineral — as was standard practice.

But the mineral wasn’t called scheelite at the time — the man wasn’t a narcissist. The mineral was called “tungsten,” from the Swedish words meaning “heavy stone.” So now, both a real-life mineral and a hypothetical element within that mineral had the name “tungsten.” The mineral was re-dubbed scheelite some time later to avoid confusion between them.⁶

In 1783, Spanish brothers Fausto and Juan Jose de Elhuyar were following up on Scheele’s work. They succeeded in isolating the pure metal — a first — but they weren’t working with the same mineral as Scheele. They had a sample of the mineral called wolframite. So they called the newly distilled element wolfram. Well, actually, they called it volfram, because the letter “W” was not part of the Spanish alphabet until 1914, but I digress.⁷ They actually argued explicitly against calling the element tungsten:

This name is more suitable than tungust or tungsten … because volfram is a mineral which was known long before the heavy stone, at least among the mineralogists, and also because the name volfram is accepted in almost all European languages, including Swedish.”

So Agricola and others made note of a mineral called wolframite, which contains tungsten, but nobody knew that at the time. Scheele suspected the existence of tungsten in a mineral that was also called tungsten then, but is now called scheelite. The de Elhuyar Brothers first isolated tungsten from the mineral wolframite, which is still called wolframite today, and they insisted that the element be called wolfram. Pretty much everyone thought that made sense, but the French and the English had already grown attached to the name tungsten. The IUPAC, ever the fans of splitting the baby, officially endorse the name tungsten and the chemical symbol W.

Most places that don’t speak French or English call this element wolfram. It’s not too surprising that the Germans and the Spanish would be rather attached to the name, but ironically, even the Swedes have given up the name tungsten.

Being an English-language program, we’ll continue calling element 74 tungsten, with the admission that “wolfram” sounds much cooler.

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If you knew only one thing about tungsten before today’s program, it’s probably that it was used as the filament in old-style incandescent light bulbs. You might also know that Thomas Edison didn’t really invent the light bulb, but you might be hard-pressed to say just who did.

That’s because the light bulb is just about the perfect example of incremental invention. It wasn’t long after Galvani and Volta published their discoveries that people started looking for a way to turn electrical energy into artificial light. One of the first to make any progress was Ebenezer Kinnersley, a Philadelphia man who palled around with Benjamin Franklin in the mid-18th century.

In 1761, Kinnersley demonstrated that a sufficiently powerful electrical current could heat a metal wire to the point that it glowed red-hot. That’s what’s called “incandescence.”⁸ It wasn’t something new — that’s the same phenomenon that makes a blacksmith’s tools glow after they’re pulled from the fire. The discovery was the fact that electricity could do the same thing. That’s great, but Kinnersley was discharging Leyden jars to cause an instantaneous phenomenon — not something that could provide illumination all night long. That was the bit that took people a long time to figure out.⁹

Given how much he loved to wave around electrodes, it makes sense that Humphry Davy got in on the action. In 1802, he chained together two thousand battery cells to run a current through a thin strip of platinum. Platinum wouldn’t melt, like Kinnersley’s wires did, but everything else about this first incandescent lamp made it impractical. It had a very short lifespan, it wasn’t bright at all, and lest we forget, platinum is and was a very expensive material.

As a proof of concept, though, it was great. Historians Robert Friedel and Paul Israel found at least twenty-two inventors who built on Davy’s work before Thomas Edison even arrived on the scene. The strip was replaced by a much thinner piece of wire — that’s the filament. The biggest improvement made during that time was the addition of a vacuum tube. The problem, see, is that toasting a piece of wire that hot causes it to oxidize and quite literally burn out. But that’s less of a problem if there’s no oxygen around. Enclose the filament in a glass globe, suck all the air out, and presto! You have a light bulb.¹⁰

Well, you have a bulb. They were still trying to figure out the light part. No one had found a suitable material for the filament yet. The scientists in Edison’s Menlo Park lab tried countless materials — from platinum and carbon to plants like cedar, hickory, and flax. Ultimately, they settled on bamboo, which made for a light bulb that lasted hundreds of hours. In other words, it was finally commercially viable.

Of course, by that point, the landscape was littered with dozens of patents for every possible permutation of light bulb, in multiple countries. But no matter — Edison was first and foremost a businessman. He didn’t shy away from a little litigation, and when things got too thorny, he outright bought the competition.

Even though he was certainly not “the inventor of the lightbulb,” Thomas Edison’s association with the invention is actually pretty well deserved. He did bring together over forty scientists who performed the actual research behind the light bulb, and besides blasting through every legal obstacle in the way, he popularized the light socket that remains standard in homes to this day, and he made power generation and electrical infrastructure practical. What he really invented was a viable market of consumers clamoring for what he was selling.

Conspicuously absent from the above list of improvements is a tungsten filament. Edison had nothing to do with that bit of tech. That was invented by William Coolidge, a scientist working for General Electric in the early 1900s. Tungsten’s incredible hardness makes it more difficult to work than most metals. By working it into an amalgam with mercury and other metals, he was able to coax ductility out of tungsten and draw it into the kind of thin wire needed for a proper filament.^{11 12}

Apparently he also couldn’t resist a good pun, either. In a letter to his parents, he wrote, “The outlook for my method is certainly very bright now.” And it was! Coolidge spent the next decade improving the tungsten filament, and by 1916, Edison’s lightbulbs were obsolete.

The lightbulb saw further advancement over the next century. For instance, the bulb didn’t actually need to house a vacuum. A vacuum is a very delicate thing. By instead filling the bulb with an inert gas like nitrogen or argon, the filament was still protected from oxidation, and the bulb itself became far less prone to breakage. But tungsten remained the heart of the household lightbulb until compact fluorescent bulbs gained popularity around the year 2000. By then, it was definitely high time for incandescent bulbs to go — they require a lot of energy to operate, since they’re actually far better as heating devices than lights. Only five percent of the electricity pumped into a tungsten bulb gets converted to light — all the rest is lost as heat. In comparison, CFLs use seventy percent less energy. Making the switch was one of the easiest ways for humanity to rein in its extravagant energy usage. We should probably do more than just change our lightbulbs, but that’s a whole other conversation.

Alas, the CFL’s time on the throne was brief, having already been surpassed both technologically and commercially by the availability of cheap, high-quality LEDs. When it comes to historical legacies, the tungsten light bulb is a juggernaut.

Yet Coolidge’s name is virtually unknown today, while Edison is known by every school-aged child in the country. There really is no justice. We can only hope that Coolidge was satisfied receiving occasional accolades from the scientific community, like the Rumford Prize, the Howard N. Potts Medal, the Louis E. Levy Medal, the Faraday Medal, the Franklin Medal, the Rontgen Medal, election to the National Inventor’s Hall Of Fame, and ironically, the American Institute Of Electrical Engineers’ Edison Medal.¹³

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Sadly, all this means you’re a couple decades too late to reliably source element 74 from one of the spare lightbulbs you keep in your linen closet — unless you’re one of those people who stockpiled years worth of incandescents before their production was phased out. That’s okay, though. Maybe it’s no longer in every room of your house, but tungsten can still be readily found. You just have to know where to look.

Sometimes, investigators are surprised to find tungsten masquerading as gold. The two metals are very similar in weight, so sometimes it can be difficult to tell the difference. In 2012, some bars of bullion were found to have had their insides drilled out and the gold replaced with tungsten.^{14 15 16}Usually this is seen as a scandal, or some kind of crime. You would surely confuse your local metals dealer if you actually wanted their gold bars to provide two element samples at once.

But you wouldn’t be the first person to seek out tungsten in a context where gold has traditionally been more desired. Recently, tungsten jewelry has been growing in popularity, particularly as an alternative material for wedding bands.¹⁷ These also tend to be strangely inexpensive — so inexpensive, in fact, that you might want to conduct some tests to make sure you haven’t actually been sold some other metal in disguise.

Like tantalum, tungsten’s properties make it ideal for use in drill bits and other power tools, often in the form of tungsten carbide. Similarly, it’s a popular favorite for use in turbines, aircraft engines, and rocket nozzles.

Sadly, tungsten can be just as effective in more destructive contexts, too. Some of these are rather predictable — bullets and defensive plating and the like. The U.S. Army recently developed some new armor-piercing tungsten bullets that only cost $13 a round!¹⁸ But the most awful wartime use of tungsten is thankfully one that remains hypothetical (for now). It involves launching a telephone pole-sized cylinder of tungsten into Earth orbit. That’s all that it is — no explosives, no radiation, just one long, solid mass of tungsten.

You see, it doesn’t need to be fancy when it’s designed to crash into the Earth at ten times the speed of sound. Guided by satellites, the orbiting rod would effectively become a weaponized meteor strike. Such a bombardment could just as easily destroy an underground bunker as a few city blocks.

The idea is called a Kinetic Energy Weapon, or, more colloquially, “Rods from God.” Effectively a weapon of mass destruction, it could, like the isomer bomb, theoretically skirt any prohibitions enacted by those pesky nuclear treaties.^{19 20}

The mastermind behind this particular idea was Jerry Pournelle, a man who became most famous for his career as a writer of science fiction in the 1970s and ’80s. But before transitioning to speculative fiction, Pournelle had a long career at Boeing, where he analyzed proposals for new weapons systems. It was actually there, not in his works of fiction, that Pournelle originally devised this one. He called it Project Thor.

So keep an eye on the sky, or at least the evening news. After all, we’re trying to help you seek out tungsten — not the other way around.

Thanks for listening to The Episodic Table of Elements. Music is by Kai Engel. To learn about Portugal’s double-dealings in the tungsten market during World War II, visit episodic table dot com slash W.

Next time, we shall sadly need to spend more time with Walter and Ida Noddack while we examine rhenium.

Until then, this is T. R. Appleton, reminding you that changing out the lightbulbs is nice and all, but if we’re concerned about climate change, we should probably do something about the one hundred companies that are responsible for 70% of global greenhouse gas emissions.²¹

1. Uncle Tungsten, p. 1-9. Oliver Sacks, 2001.
2. Advanced Refractory Metals, What Is The Most Refractory Metal In The World?
3. ChinaTungsten Online, Tungsten Powder Metallurgy: Sintering.
4. Tungsten: Properties, Chemistry, Technology Of The Element, Alloys, And Chemical Compounds, p. 77 – 79. Erik Lassner and Wolf-Dieter Schubert, 2012.
5. Elementymology & Elements Multidict, Wolframium Tungsten. Peter van der Krogt.
6. MineralExpert.org, Scheelite – The Fluorescent Tungsten Ore. Vic Ridgley, November 22, 2018.
7. ThoughtCo., The Spanish Alphabet. Gerald Erichsen, May 26, 2019.
8. Encyclopedia Britannica, Incandescence.
9. Copper Wire And Electrical Conductors: The Shaping Of A Technology, p. 126-128. Barrie Charles Blake-Coleman, 1992.
10. Energy.gov, The History Of The Light Bulb. November 22, 2013.
11. American Scientist, Tungsten’s Brilliant, Hidden History. Ainissa Ramirez.
12. Encyclopedia Britannica, William D. Coolidge. Last updated October 19, 2020.
13. Edison Tech Center, William D. Coolidge.
14. Forbes, The Drilled Gold Bars Filled With Tungsten. Tim Worstall, March 26, 2012.
15. Reuters, The Problem Of Fake Gold Bars. Felix Salmon, March 25, 2015.
16. United States Gold Bureau, Gold Investors Warned To Watch Out For Fake Tungsten Bars. May 22, 2012.
17. The Periodic Table: A Visual Guide To The Elements, these pages. Paul Parsons, 2014.
18. Department Of Defense Fiscal Year (FY) 2019 Budget Estimates, February 2018.
19. Popular Science, Rods From God. Eric Adams, June 1, 2004.
20. The New York Times Magazine, Rods From God. Jonathan Shainin, December 10, 2016.
21. The Guardian, Just 100 Companies Responsible For 71% Of Global Emissions, Study Says. Tess Riley, July 10, 2017.