Pierre and Marie Curie refine radium chloride.

Pierre Curie was a French physicist and chemist, and a pioneer in crystallography, magnetism, and radioactivity. He shared one half of the 1903 Nobel Prize in Physics with his wife Marie Curie "in recognition of the extraordinary services they have rendered by their joint researches on the radiation phenomena discovered by Professor Henri Becquerel". With their win, the Curies became the first married couple to win a Nobel Prize, launching the Curie family legacy of five Nobel Prizes.

Maria Salomea Skłodowska-Curie, known as Marie Curie, was a Polish and naturalised-French physicist and chemist who conducted pioneering research on radioactivity.

Radium chloride is an inorganic compound with the chemical formula RaCl₂. It is a radium salt of hydrogen chloride. It was the first radium compound isolated in a pure state. Marie Curie and André-Louis Debierne used it in their original separation of radium from barium. The first preparation of radium metal was by the electrolysis of a solution of this salt using a mercury cathode.