Radium

Radium (Ra) was discovered in the ore pitchblende by the French chemists Marie and Pierre Curie and an assistant in 1898. It is a radioactive element, classified as an alkaline earth metal in the periodic table. It is found naturally in uranium and thorium ores, and when isolated, it is a slivery, lustrous, and soft metal. Radium is formed by the radioactive disintegration of uranium. Radiation fr...