In 1994, when Edouard Meylan turned 18 years old, his parents gave him an Audemars Piguet Royal Oak wristwatch housed in a 33-millimeter case made of tantalum, a rare and hard metal with an unusual blue-grey sheen.
To Mr. Meylan, now chief executive of the independent watchmaker H. Moser & Cie, the watch, which came on a two-tone steel and tantalum bracelet, was something of an enigma.
“It had two colors: light gray and dark gray,” he said on a recent phone call from Moser’s headquarters in Schaffhausen, Switzerland. “I kept wondering which metal is which? Why is it so heavy?
“I kind of fell in love with tantalum. It became a dream of mine to create our Streamliner model in a tantalum case and bracelet.”
For a metal that is, by all accounts, nightmarishly difficult to work with, tantalum has earned a cult following in the high-end watch trade where a small but steady stream of brands, including F.P. Journe and Urwerk, have embraced it, even if only for their most special timepieces.
Discovered in 1802 by the Swedish chemist Anders Gustaf Ekeberg, tantalum is an element (Ta, atomic symbol 73) characterized by its density: 16.4 grams per centimeter cubed, compared with about 7.85 for steel. Its melting point of 3,017 degrees Celsius (5,463 degrees Fahrenheit) is extremely high, and it is resistant to acids.
That last characteristic inspired Mr. Ekeberg to name it after Tantalus, the king in Greek mythology condemned by Zeus to forever stand in a pool of water he could never drink, surrounded by fruit he could never reach.
As part of a class called refractory metals, which includes niobium, tungsten and molybdenum, tantalum is highly resistant to wear. That explains why it is most often used in the capacitors of electronic devices such as mobile phones, laptops and automotive circuitry. Its compatibility with living tissue and chemical inertness also makes it suitable for surgical equipment and artificial joints.
While nowhere near as costly as gold, which sells for more than $2,000 per ounce, tantalum is considered an expensive metal, according to Ian Margerison, executive marketing manager and technical officer of the Tantalum-Niobium International Study Center, an organization in Brussels that arranges an annual conference for the tantalum trade.
“It’s not traded on any open market,” Mr. Margerison said on a phone call from his home in the English county of Devon.
“The information you will see is spot market transactions,” he said.
A 2023 price list provided by Argus Media, a private company in London that covers the global energy and commodities markets, indicated that a pound of tantalum ranged in price from $131 to $182. The Democratic Republic of Congo is the world’s largest source of tantalum ore, the raw material.
Among watchmakers, however, tantalum is sought after for its aesthetic appeal and its exclusivity, despite its substantial machining challenges.
In 2022, the brothers Bart and Tim Grönefeld of the independent Dutch brand Grönefeld introduced their 1941 Grönograaf in tantalum — a limited edition of 25 pieces, each priced at 165,000 euros ($179,725). When they made the watch available online, it sold out within a few hours.
“I love tantalum and I also love platinum,” Bart Grönefeld said. “We have worked with both, but still I tend to go for tantalum because it’s nonprecious, but still very precious in the way it’s worked with.
“Everybody knows gold, even when you’re not into watches. Everybody knows steel. Many people know titanium. But hardly anyone knows tantalum.”
Casemakers who have experimented with the metal — and have vowed to never do so again — are a notable exception.
Martin Frei, a co-founder and chief designer of the avant-garde Swiss watchmaker Urwerk, learned that the hard way a few years ago when he decided to use tantalum for the brand’s final UR-105 model (the 2021 Tantalum Hull). He had to convince the brand’s machinists, who had worked with the metal on the 2012 Urwerk model UR-110 TTH, to work with it again.
“Tantalum has a strange quality that destroys the tools — it’s almost sticky,” Mr. Frei said recently. “They somehow get clumped and break because they get too hot. But the metal itself is beautiful.”
Mr. Margerison echoed the complexities of working with the metal.
“To actually make a watch in tantalum is very difficult,” he said. “It’s like trying to machine a metallic Plasticine.”
Pierre Halimi, general manager for the Americas at F.P. Journe, said that polishing tantalum was the real challenge, necessitating techniques more akin to lapidary work than standard precious metal polishing.
“As a point of comparison, if gold is difficult to the level of 100, platinum would be 200 and tantalum 600,” he wrote in an email.
And yet, F.P. Journe has used tantalum since 2009, when it introduced the Chronomètre Bleu, a gunmetal-gray wristwatch with a chrome blue dial. The model, which is still in production, has since been joined by a handful of one-of-a-kind pieces in tantalum, all designed for various editions of the biennial Only Watch charity auction.
In June 2023, the Chronomètre Furtif Bleu in tantalum was added to the group (the 2023 auction was canceled, so the watch is being held at the factory until the event’s future is determined).
Time and again, watchmakers who have used tantalum said the metal proved so seductive, they were willing to cope with its difficulties.
Mr. Meylan said he pitched the idea of a Streamliner encased in tantalum to his team in 2017.
“We started asking around and no one wanted to work with us” on fabricating the case in tantalum, he said. “Then we found a friend in the Vallée de Joux who had a machine and told us he could do it. Two years later he gave up — ‘It’s impossible.’
“When we started exploring tantalum, my team found some people who quoted 17 times the cost of working in steel.”
A year ago, Mr. Meylan finally saw his tantalum dream come to fruition, though not in a Streamliner case. Last February, H. Moser introduced the Endeavour Perpetual Calendar Tantalum Blue Enamel, a minimalist timepiece with a movement complicated enough to justify the model’s $82,500 price.
Jean Arnault, director of watches at Louis Vuitton, encountered the same commercial challenges as Mr. Meylan, so instead of making a production model, he decided to make a one-off tantalum Tambour for himself.
At a media event in October in Montecito, Calif., Mr. Arnault — the youngest son of Bernard Arnault, the founder, chairman and chief executive of LVMH Moët Hennessy Louis Vuitton, the world’s largest luxury goods company — wore the unique piece, explaining that while it did not make economic sense to produce an entire collection in tantalum, he admired the way what he called the metal’s “curious shade” paired with the blue sapphires around the bezel.
“It’s an elusive metal that no one really knows about, which is quite fun,” he said. “It’s just the machining challenges. It breaks the tools very easily. And then you can break the machines because the tools break. So it’s a bit of a vicious circle.
“But that’s what watch lovers love, right? The harder it is to do, the better people like to do it.”
Omega is one of the few brands that has used tantalum for models in regular production. In 1993, the watchmaker introduced its Seamaster 300M chronograph in a combination of titanium, tantalum and 18-karat red gold; it was discontinued in 2003.
In 2018, to celebrate the 25th anniversary of the Seamaster Diver 300M, the brand introduced a $14,500 limited edition of 2,500 pieces featuring tantalum on the base of the bezel and the middle links of the bracelet. And two years later, a new $23,000 Seamaster 300M chronograph — much like the original 1993 version, with parts of its bezel and bracelet made of tantalum — joined the collection.
Robert-Jan Broer, founder and editor of the online watch publication Fratello Watches, bought the original Omega model secondhand in 2017, after lusting after it for years.
“If you look at it from far away, you don’t see the difference between the tantalum and titanium, but if you look closer, it has this weird bluish hue,” Mr. Broer said.
He said he appreciated the “heft” of the timepiece, while questioning why brands would go to such lengths to use tantalum. “Just for the sake of using a material that’s exclusive or rare?” Mr. Broer said. “Because for the wearer there’s not much of a difference.”
Mr. Frei of Urwerk offered one rationale, closely related to the philosophy he and the brand’s co-founder, Felix Baumgartner, embraced when they founded their brand in 1997 and named it after the ancient Sumerian city of Ur, where time keeping is said to have begun.
“We think of tantalum as an ‘Urwerkian’ metal because it is a pure element and its creation goes back to the beginning of time,” Mr. Frei said. “We have the Ur, the Big Bang, the moment where everything starts. Playing with these materials created in this moment is fascinating.”
“And the color is dark and appealing,” he noted. “It has an energy within it. But of course, because it’s quite heavy, people maybe think when they try it on that it’s too heavy.”
Mr. Meylan, however, was more ambivalent. “Our objective was to produce 50 cases, and we fulfilled that dream, but I don’t think we’ll make another watch in tantalum,” he said.
“I still dream of doing a tantalum Streamliner, but maybe it’ll be a retirement gift for myself.”