Pitchblende also known as uraninite is mined in many parts of the world including the United States Although Curie felt disadvantaged by the inadequate facilities she got to work The shed had no vent hoods to carry away poisonous gases so Curie began the first part of her operation outdoors In bad weather she brought everything indoors and opened the windows The first stage of separating the pitchblende involved boiling and melting the ore in a large cauldron Working with 45-pound 8
20 kg batches Curie spent entire days stirring the mixture with an iron rod almost as big as she was She later admitted this work left her broken with fatigue at the day’s end 3 Once the mixture was melted Curie added acids to dissolve the salts in the solution This was followed by more boiling and more chemical treatments filtering pulverizing dissolving and crystallizing until more and more elements had been separated from the pitchblende The various component elements were placed into jars and stored around the lab Gradually Curie produced a substance with greater and greater concentrations of radium As the difficult labor continued Curie hired an assistant Later a factory owner offered to perform the early stages of purification at his facilities Then he would send the resulting product to Curie who still carried out the later more precise stages herself Curie and Pierre had originally estimated that the process of purifying enough material to establish an atomic weight would take a few weeks Instead the Theoretical Interest Not everyone saw the purpose of Curie’s work in isolating radium Even her father Władysław Skłodowska a teacher who first introduced her to a love of physics questioned the effort she put into her discovery In a letter to her he wrote You are now in possession of pure radium salts If we consider the amount of work done in obtaining this it would certainly be the most expensive of chemical elements What a pity it is that this work has only theoretical interest 4 He died six days later never learning how wrong he was 9
Small but Powerful When Curie began her work with pitchblende she estimated radium would make up approximately 1 100 of the mineral Instead it made up 1 1,000,000 of pitchblende This is why so many tons of the mineral had to be processed to produce just 0 10 gram of radium Although Curie knew radium would be more powerful than uranium she hadn’t guessed just how much more powerful Its radiation is five million times more intense than uranium’s 7 work stretched to four years Despite the difficulty of the task Curie felt that these were the happiest days of her life Later she wrote We were very happy in spite of the difficult conditions under which we worked A great tranquility reigned in our poor shabby hangar occasionally while observing an operation we would walk up and down talking of our work present and future We lived in a preoccupation as complete as that of a dream 5 Even after their busy days in the lab Curie and Pierre often left their daughter in the care of Pierre’s father and walked back to the lab at night There they paused to admire the jars of radium that according to Curie glowed blue in the dark like faint fairy light 6 SUCCESS Finally on March 28 1902 after processing more than eight short tons 7 3 metric tons of pitchblende Curie had isolated 0 10 gram of pure radium Although this amount would fill only 1 50 of a teaspoon it was enough for Curie to calculate the The shed that Curie used as a lab was very minimal and lacked basic comforts 10
