In this article, documents relating to the history of the Radium Committee of the Royal Society are collated for the first time. Founded in 1903, the committee had its status enhanced in 1904, when the Goldsmiths' Company donated £1000 for the establishment of a Radium Research Fund. Two years later the fund was used to purchase 500 kg of pitchblende residues from the Austrian government. The French chemist Armet de Lisle was contracted to perform the first stage of extraction, and the process of purification was performed at the Government Laboratory during 1907 by the Government Analyst, T. E. Thorpe, yielding an estimated 70 mg of radium chloride. In 1914 the unexpended balance of about £500 was awarded to Ernest Rutherford, but the bulk was not used until 1921, when Rutherford had moved to Cambridge. The fund was then used to purchase radium that had been on loan to him from Austria before World War I. After Rutherford's death in 1937 the Committee was wound up, and the Society's radium was controlled on a more
ad hoc
basis. After Thorpe's work in 1907, the radium was lent out successively to several leading scientists until its existence was last recorded in 1953.