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Radium is a decay product of uranium and is therefore found in all uranium-bearing ores. Radium was originally acquired from pitchblende ore from Joachimsthal, Bohemia (7 metric tons of pitchblende yields 1 gram of radium). Carnotite sands in Colorado provide some of the element, but richer ores are found in the Democratic Republic of the Congo, the Great Lakes area of Canada and can also be extracted from uranium processing waste. Large uranium deposits are located in Ontario, New Mexico, Utah, Australia, and in other places.
Its compounds color flames crimson carmine (rich red or crimson color with a shade of purple) and give a characteristic spectrum. Due to its very short half life and intense radioactivity, radium compounds are quite rare, occurring almost exclusively in uranium ores.
Fluorides: radium (II) fluoride (Ra F2), Chlorides: radium (II) chloride (Ra Cl2), Bromides: radium (II) bromide (Ra Br2), Iodides: radium (II) iodide (Ra I2), Hydrides: no data, Oxides: radium (II) oxide (Ra O), Sulfides: no data, Selenide s: no data, Tellurides: no data, Nitride s: no dataRadium has 25 different isotopes, four of which are found in nature, with radium-226 being the most common and stable. Ra-223, Ra-224, Ra-226 and Ra-228 are all generated in the decay of either U or Th. Ra-226 is a product of U-238 decay, and is the longest-lived isotope of Ra with a half-life of 1602 years; next longest is Ra-228, a product of Th-232 breakdown, with a half-life of 6.7 years.
Radium is over 1 million times more radioactive than the same amount of uranium. Its decay occurs in at least seven stages; the successive main products have been studied and are called radium emanation or exradio, radium A, radium B, radium C, etc. (The emanation is a heavy gas, the later products are solids.) These products are regarded as unstable elements, each with an atomic weight a little lower than its predecessor.
Radium loses about 1% of its activity in 25 years, being transformed into elements of lower atomic weight with lead being a final product of disintegration. The curie is defined as that amount of radioactivity which has the same disintegration rate as 1 gram of Ra-226 (3.7 x 1010 disintegrations per second).
Radium is extremely radioactive and its decay product, radon is a radioactive gas. Since Ra is closely related to calcium, it has the potential to cause great harm by substituting it in bone. Inhalation, injection, or body exposure to radium can cause cancer and other body disorders. Stored radium should be ventilated to prevent build-up of radon.
Emitted energy from the decay of radium ionizes gases, affects photographic plates, causes sores on the skin, and produces many other dramatic effects.
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