Sometimes I had to spend a whole day mixing a boiling mass with a heavy iron rod nearly as large as myself. I would be broken with fatigue at the day's end. Other days, on the contrary, the work would be a most minute and delicate fractional crystallization, in the effort to concentrate the radium.

In 1903, I finished my doctor's thesis and obtained the degree. At the end of the same year, the Nobel prize was awarded jointly to Becquerel, my husband and me for the discovery of radioactivity and new radioactive elements.

The first experiments on the biological properties of radium were successfully made in France, with samples from our laboratory, while my husband was living.

Marie Curie Quotes