Sam Kean
Page 20
After the war, they resumed their partnership, but while the decades between the wars were thrilling in Germany scientifically, they proved scary politically. Hahn—strong-jawed, mustached, of good German stock—had nothing to fear from the Nazi takeover in 1932. Yet to his credit, when Hitler ran all the Jewish scientists out of the country in 1933—causing the first major wave of refugee scientists—Hahn resigned his professorship in protest (though he continued to attend seminars). Meitner, though raised a proper Austrian Protestant, had Jewish grandparents. Characteristically, and perhaps because she had at last earned her own real research lab, she downplayed the danger and buried herself in scintillating new discoveries in nuclear physics.
The biggest of those discoveries came in 1934, when Enrico Fermi announced that by pelting uranium atoms with atomic particles, he had fabricated the first transuranic elements. This wasn’t true, but people were transfixed by the idea that the periodic table was no longer limited to ninety-two entries. A fireworks display of new ideas about nuclear physics kept scientists busy around the world.
That same year, another leader in the field, Irène Joliot-Curie, did her own bombardments. After careful chemical analysis, she announced that the new transuranic elements betrayed an uncanny similarity to lanthanum, the first rare earth. This, too, was unexpected—so unexpected that Hahn didn’t believe it. Elements bigger than uranium simply could not behave exactly like a tiny metallic element nowhere near uranium on the periodic table. He politely told Frédéric Joliot-Curie that the lanthanum link was hogwash and vowed to redo Irène’s experiments to show that the transuranics were nothing like lanthanum.
Also in 1938, Meitner’s world collapsed. Hitler boldly annexed Austria and embraced all Austrians as his Aryan brethren—except anyone remotely Jewish. After years of willed invisibility, Meitner was suddenly subject to Nazi pogroms. And when a colleague, a chemist, tried to turn her in, she had no choice but to flee, with just her clothes and ten deutsch marks. She found refuge in Sweden and accepted a job at, ironically, one of the Nobel science institutes.
Despite the hardships, Hahn remained faithful to Meitner, and the two continued to collaborate, writing letters like clandestine lovers and occasionally rendezvousing in Copenhagen. During one such meeting in late 1938, Hahn arrived a little shaken. After repeating Irène Joliot-Curie’s experiments, he had found her elements. And they not only behaved like lanthanum (and another nearby element she’d found, barium), but, according to every known chemical test, they were lanthanum and barium. Hahn was considered the best chemist in the world, but that finding “contradict[ed] all previous experience,” he later admitted. He confessed his humbling bafflement to Meitner.
Meitner wasn’t baffled. Out of all the great minds who worked on transuranic elements, only hard-eyed Meitner grasped that they weren’t transuranic at all. She alone (after discussions with her nephew and new partner, physicist Otto Frisch) realized that Fermi hadn’t discovered new elements; he’d discovered nuclear fission. He’d cracked uranium into smaller elements and misinterpreted his results. The eka-lanthanum Joliot-Curie had found was plain lanthanum, the fallout of the first tiny nuclear explosions! Hevesy, who saw early drafts of Joliot-Curie’s papers from that time, later reminisced on how close she’d come to making that unimaginable discovery. But Joliot-Curie, Hevesy said, “didn’t trust herself enough” to believe the correct interpretation. Meitner trusted herself, and she convinced Hahn that everyone else was wrong.
Naturally, Hahn wanted to publish these astounding results, but his collaboration with, and debt to, Meitner made doing so politically tricky. They discussed options, and she, deferential, agreed to name just Hahn and his assistant on the key paper. Meitner and Frisch’s theoretical contributions, which made sense of everything, appeared later in a separate journal. With those publications, nuclear fission was born just in time for Germany’s invasion of Poland and the start of World War II.
So began an improbable sequence of events that culminated in the most egregious oversight in the history of the Nobel Prize. Even without knowledge of the Manhattan Project, the Nobel committee had decided by 1943 to reward nuclear fission with a prize. The question was, who deserved it? Hahn, clearly. But the war had isolated Sweden and made it impossible to interview scientists about Meitner’s contributions, an integral part of the committee’s decision. The committee therefore relied on scientific journals—which arrived months late or not at all, and many of which, especially prestigious German ones, had barred Meitner. The emerging divisions between chemistry and physics also made it hard to reward interdisciplinary work.
After suspending the prizes in 1940, the Swedish Academy began awarding a few retroactively in 1944. First up, at long last, Hevesy won the vacant 1943 prize for chemistry—though perhaps partly as a political gesture, to honor all refugee scientists. In 1945, the committee took up the more vexed matter of fission. Meitner and Hahn both had strong back-room advocates on the Nobel committee, but Hahn’s backer had the chutzpah to point out that Meitner had done no work “of great importance” in the previous few years—when she was in hiding from Hitler. (Why the committee never directly interviewed Meitner, who was working at a nearby Nobel institute, isn’t clear, although it’s generally bad practice to interview people about whether they deserve a prize.) Meitner’s backer argued for a shared prize and probably would have prevailed given time. But when he died unexpectedly, the Axis-friendly committee members mobilized, and Hahn won the 1944 prize alone.
Shamefully, when Hahn got word of his win (the Allies now had him in military custody for suspicion of working on Germany’s atomic bomb; he was later cleared), he didn’t speak up for Meitner. As a result, the woman he’d once esteemed enough to defy his bosses and work with in a carpentry shop got nothing—a victim, as a few historians had it, of “disciplinary bias, political obtuseness, ignorance, and haste.”*
The committee could have rectified this in 1946 or later, of course, after the historical record made Meitner’s contributions clear. Even architects of the Manhattan Project admitted how much they owed her. But the Nobel committee, famous for what Time magazine once called its “old-maid peevishness,” is not prone to admit mistakes. Despite being repeatedly nominated her whole life—by, among others, Kazimierz Fajans, who knew the pain of losing a Nobel better than anyone—she died in 1968 without her prize.
Happily, however, “history has its own balance sheet.” The transuranic element 105 was originally named hahnium, after Otto Hahn, by Glenn Seaborg, Al Ghiorso, and others in 1970. But during the dispute over naming rights, an international committee—as if hahnium was Poland—stripped the element of that name in 1997, dubbing it dubnium. Because of the peculiar rules for naming elements*—basically, each name gets one shot—hahnium can never be considered as the name for a new element in the future, either. The Nobel Prize is all Hahn gets. And the committee soon crowned Meitner with a far more exclusive honor than a prize given out yearly. Element 109 is now and forever will be known as meitnerium.
13
Elements as Money
If the periodic table has a history with politics, it has an even longer and cozier relationship with money. The stories of many metallic elements cannot be told without getting tangled up in the history of money, which means the history of those elements is also tangled up with the history of counterfeiting. In different centuries, cattle, spices, porpoise teeth, salt, cocoa beans, cigarettes, beetle legs, and tulips have all passed for currency, none of which can be faked convincingly. Metals are easier to doctor. Transition metals especially have similar chemistries and densities because they have similar electron structures, and they can blend together and replace one another in alloys. Different combinations of precious and less-than-precious metals have been fooling people for millennia.
Around 700 BC, a prince named Midas inherited the kingdom of Phrygia in what is now Turkey. According to various myths (which might conflate two rulers named Midas), he led an eventful life. J
ealous Apollo, the god of music, asked Midas to judge a showdown between him and the other great lyre strummers of the era, then turned Midas’s ears into donkey ears when Midas favored someone else over Apollo. (He didn’t deserve human ears if he judged music that badly.) Midas also reportedly maintained the best rose garden in the ancient world. Scientifically, Midas sometimes receives credit for discovering tin (not true, though it was mined in his kingdom) and for discovering the minerals “black lead” (graphite) and “white lead” (a beautiful, bright white, poisonous lead pigment). Of course, no one would remember Midas today if not for another metallurgical novelty, his golden touch. He earned it after tending to the drunken satyr Silenus, who passed out in his rose garden one night. Silenus so appreciated the monarch’s hospitality that he offered Midas a reward. Midas asked that whatever he touched transform into gold—a delight that soon cost him his daughter when he hugged her and almost cost him his life, since for a time even food transubstantiated into gold at his lips.
Obviously, none of that probably ever happened to the real king. But there’s evidence that Midas earned his legendary status for good reason. It all traces back to the Bronze Age, which began in Midas’s neighborhood around 3000 BC. Casting bronze, an alloy of tin and copper, was the high-tech field of the day, and although the metal remained expensive, the technology had penetrated most kingdoms by the time of Midas’s reign. The skeleton of a king popularly called Midas (but proved later to be his father, Gordias) was found in its tomb in Phrygia surrounded by bronze cauldrons and handsome bronze bowls with inscriptions, and the otherwise naked skeleton itself was found wearing a bronze belt. But in saying “bronze,” we need to be more specific. It’s not like water, where two parts hydrogen always combine with one part oxygen. A number of different alloys with different ratios of metals all count as bronze, and bronze metals around the ancient world differed in color depending on the percentages of tin, copper, and other elements where the metals were mined.
One unique feature of the metallic deposits near Phrygia was the abundance of ores with zinc. Zinc and tin ores commonly commingle in nature, and deposits of one metal can easily be mistaken for the other. What’s interesting is that zinc mixed with copper doesn’t form bronze; it forms brass. And the earliest known brass foundries existed in, of all places, the part of Asia Minor where Midas once reigned.
Is it obvious yet? Go find something bronze and something brass and examine them. The bronze is shiny, but with overtones of copper. You wouldn’t mistake it for anything else. The shine of brass is more alluring, more subtle, a little more… golden. Midas’s touch, then, was possibly nothing more than an accidental touch of zinc in the soil of his corner of Asia Minor.
To test that theory, in 2007 a professor of metallurgy at Ankara University in Turkey and a few historians constructed a primitive Midas-era furnace, into which they loaded local ores. They melted them, poured the resulting liquid into molds, and let it cool. Mirabile dictu, it hardened into an uncannily golden bullion. Naturally, it’s impossible to know whether the contemporaries of King Midas believed that his precious zinc-laden bowls and statues and belts were actually gold. But they weren’t necessarily the ones making up legends about him. More probably, the Greek travelers who later colonized that region of Asia Minor simply grew smitten with the Phrygian “bronzes,” so much brighter than their own. The tales they sent home could have swelled century by century, until golden-hued brass transmuted into real gold, and a local hero’s earthly power transmuted into the supernatural power to create precious metals at a touch. After that, it took only the genius of Ovid to touch up the story for his Metamorphoses, and voilà: a myth with a more-than-plausible origin.
An even deeper archetype in human culture than Midas is the lost city of gold—of travelers in far-off, alien lands stumbling onto unimaginable wealth. El Dorado. In modern and (slightly) more realistic times, this dream often takes the form of gold rushes. Anyone who paid an iota of attention in history class knows that real gold rushes were awful, dirty, dangerous affairs, with bears and lice and mine collapses and lots of pathetic whoring and gambling. And the chances that a person would end up rich were almost zilch. Yet almost no one with an iota of imagination hasn’t dreamed of throwing over everything in his humdrum life and rushing off to prospect for a few pure nuggets. The desire for a great adventure and the love of riches are practically built into human nature. As such, history is dotted with innumerable gold rushes.
Nature, naturally, doesn’t want to part with her treasure so easily, so she invented iron pyrite (iron disulfide) to thwart amateur prospectors. Perversely, iron pyrite shines with a luster more golden than real gold, like cartoon gold or gold in the imagination. And more than a few greenhorns and people blinded by greed have been taken in during a fool’s gold rush. But in all of history, probably the most confounded gold rush ever took place in 1896, on rough frontier land in the Australian outback. If iron pyrite is faux gold, then this gold rush in Australia—which eventually found desperate prospectors knocking down their own chimneys with pickaxes and sifting through the rubble—was perhaps the first stampede in history caused by “fool’s fool’s gold.”
Three Irishmen, including Patrick (Paddy) Hannan, were traversing the outback in 1893 when one of their horses lost a shoe twenty miles from home. It might have been the luckiest breakdown in history. Within days, without having to dig an inch into the dirt, they’d collected eight pounds of gold nuggets just walking around. Honest but dim, the trio filed a claim with territory officials, which put the location on public record. Within a week, hundreds of prospectors were storming Hannan’s Find, as the post became known, to try their luck.
In a way, the expanse was easy pickings. During those first months in the desert, gold was more plentiful than water. But while that sounds great, it wasn’t. You can’t drink gold, and as more and more miners piled in, the prices of supplies soared, and competition for mining sites grew fierce. People started having to dig for gold, and some fellows figured out there was easier money to be had in building up a real town instead. Breweries and brothels popped up in Hannan’s Find, as did houses and even paved roads. For bricks, cement, and mortar, builders collected the excess rock dug out during excavations. Miners just cast it aside, and as long as they were going to keep digging, there was nothing better to do with the rubble.
Or so they assumed. Gold is an aloof metal. You won’t find it mixed inside minerals and ores, because it doesn’t bond with other elements. Its flakes and nuggets are usually pure, besides a few odd alloys. The exception, the single element that will bond to gold, is tellurium, a vampirish element first isolated in Transylvania in 1782. Tellurium combines with gold to form some garish-sounding minerals—krennerite, petzite, sylvanite, and calaverite—with some equally atrocious chemical formulas. Instead of nice proportions such as H2O and CO2, krennerite is (Au0.8, Ag0.2)Te2. Those tellurides vary in color, too, and one of them, calaverite, shines sort of yellow.
Actually it shines more like brass or iron pyrite than deep-hued gold, but it’s probably close enough to trick you if you’ve been out in the sun all day. You can imagine a raw, dirty eighteen-year-old hauling in calaverite nuggets to the local appraiser in Hannan’s Find, only to hear the appraiser dismiss them as a sackful of what mineralogists classify as bagoshite. Remember, too, that some tellurium compounds (not calaverite, but others) smell pungent, like garlic magnified a thousand times, an odor notoriously difficult to get rid of. Better to sell it and bury it in roads, where it won’t stink, and get back to digging for the real McCoy.
But people just kept piling into Hannan’s Find, and food and water didn’t get any cheaper. At one point, tensions over supplies ran so high that a full-on riot erupted. And as things got desperate, rumors circulated about that yellowish tellurium rock they were digging up and throwing away. Even if hardscrabble miners weren’t acquainted with calaverite, geologists had been for years and knew its properties. For one, it decomposes at low temperatures,
which makes separating out the gold darn easy. Calaverite had first been found in Colorado in the 1860s.* Historians suspect that campers who’d built a fire one night noticed that, um, the rocks they’d ringed the fire pit with were oozing gold. Pretty soon, stories to that effect made their way to Hannan’s Find.
Hell finally broke loose on May 29, 1896. Some of the calaverite used to build Hannan’s Find contained five hundred ounces of gold per ton of rock, and miners were soon tearing out every damn ounce they could find. People attacked refuse heaps first, scrabbling among them for discarded rock. When those were picked clean, they went after the town itself. Paved-over potholes became potholes again; sidewalks were chiseled out; and you can bet the miner who built the chimney and hearth for his new home out of gold telluride–infused brick wasn’t too sentimental about tearing it apart again.