May 20, 1921: Marie Curie receives a gram of radium from U.S. President Harding

In 1920, as the world was still recovering from World War I, two-time Nobel laureate Marie Curie was trying to get her lab up and running.

The Radium Institute in Paris had been finished shortly before the war broke out, but its research had been put on pause: The lab’s male employees were sent to the front lines, while Curie made her own wartime contribution by developing mobile X-ray units for the battlefield.

But amid this new decade marked by fragile peace across Europe, Curie found herself facing a new roadblock: She didn’t have enough radium for her research on radium’s fundamental properties, and its usefulness for medical imaging and cancer treatments.

It was this pressing need that would lead Curie to travel halfway across the world for her first of two official visits to the United States. While her inaugural tour was replete with pomp and circumstance, it also allowed Curie to connect with scientists and see the impact of her work — and to this day, it highlights the humanitarian side of Curie’s legacy.

In 1920, during an interview for The Delineator magazine, journalist and socialite Marie Mattingly Meloney asked Curie, “If you had the whole world to choose from, what would you take?” Curie replied, “I would wish for a gram of radium to facilitate my research.”

This response “shocked” Meloney, said Dava Sobel, author of The Elements of Marie Curie: How the Glow of Radium Lit a Path for Women in Science, as Meloney realized that Curie, “who was doing such important work and was responsible for all the good that was happening because of this discovery,” had so little of this essential chemical.

“Mrs. Meloney decided she was going to raise money to buy [Curie] another gram of radium and then bring her to the United States and tour her around,” said Sobel. Meloney launched the Marie Curie Radium Fund and raised $100,000 — around $1.2 million today when adjusted for inflation — to pay for what was then a “vast quantity” of radium, Sobel said.

Curie arrived in New York on May 11, 1921, and, accompanied by her daughters Irène and Ève, embarked on a six-week tour of the U.S., including stops in Washington, D.C., Philadelphia, Pittsburg, Chicago, and Boston. Along the way, Curie delivered lectures and visited more than 15 universities and research institutions.

“There were all these big galas at [places like] Carnegie Hall and the Waldorf Astoria, and it was really not a lifestyle that [Curie] was accustomed to,” said Sobel, adding that Curie would occasionally send one of her daughters to the receptions in her place. “It seems that only part of the trip that [Curie] really enjoyed were when she got to meet with scientists.”

One of the highlights for Curie included a visit to the Standard Chemical Company’s ore processing plant, now a disposal site managed by the U.S. Department of Energy, located 20 miles southwest of Pittsburg. Curie explicitly asked to see the plant, one of the world’s largest radium producers in the early 1920s, where Curie “had the satisfaction of seeing that the procedures that she had pioneered were still in use,” said Sobel.

Curie also mentioned her visit to the National Bureau of Standards in Washington, D.C., now known as the National Institute of Standards and Technology, where she met with scientists and dedicated a low-temperature experiment lab. In the biography of her late husband Pierre, Curie wrote of her time spent with the institute’s scientists: “The hours I spent in their company are among the best of my travel.”

On May 20, 1921, Curie was the guest of honor for an audience of cabinet officers, supreme court judges, and foreign diplomats at the White House. It was during this official ceremony where she received a key to the box that housed her precious radioactive cargo and a Certificate for Radioactive Material from the U.S. Bureau of Standards from President Warren Harding, who presented Curie with the gift on behalf of the “women of America” and in recognition of Curie’s “transcendent service to science and humanity.”

Curie was deeply moved by the ceremony, as she reflected in Pierre’s biography. “A remembrance never to be forgotten was left by this reception in which the chief representative of a great nation offered me homage of infinite value, the testimonial of the recognition of his country's citizens,” she wrote.

The radium itself was not actually present during the ceremony, although a replica of the box and its glass tubes was set up in the White House’s East Room. Instead, the radium was measured and certified by scientists at the National Bureau of Standards, then packed into ten tubes and placed inside a chronometer box to safeguard it for the voyage back to Paris.

Curie returned home on June 25, 1921, where the Radium Institute would go on to become a major radioactivity research center, producing four additional Nobel prize winners — including one of her daughters, Irène Joliot-Curie.

Curie came back to the U.S. in 1929, not for radium but for money to purchase a gram of the chemical that she would use to start a new radium institute in Poland. Her visit to the Herbert Hoover White House garnered less media attention, likely overshadowed by the recent stock market crash before the Great Depression.

While Curie remains one of the world’s most famous scientists, Sobel said that her first U.S. tour also highlights the humanitarian side of her work.

“We think of her as a scientist, but she was also instrumental in the discovery of the cure for cancer,” said Sobel, alluding to Curie and her husband’s discovery that radium killed diseased cells faster than healthy ones. Sobel likened Curie to Jonas Salk, the virologist who developed the polio vaccine, for their shared desire not to profit from science but to have their research benefit humanity — and, in a different way, to Einstein. “Similar to the way people reacted to Einstein — they didn’t understand what he did, but there was something about him that was so compelling — [Curie] had that kind of stature,” Sobel added.

Curie touched on this idea in her husband’s biography. “If the discovery of radium has so much sympathy in America, it is not only because of its scientific value, and of the importance of medical utilization; it is also because the discovery has been given to humanity without reservation or material benefits to the discoverers,” she wrote.