Radium

Radium, Ra, 88, is a radioactive alkali-earth metal, chemically similar to the other alkali-earths, including calcium and barium. Radium became famous in the early 1900s to 1930s, because it was thought to be a magic chemical that solved every problem, and created infinite energy. This isn't exactly true, but radium does have numerous interesting uses.

Radium only has a half-life of 1600 years(see more about half-lives on the Radioactivity page), meaning in about 5000 years almost all of it will have decayed into radon gas, however it is somewhat common because it is a decay product of uranium, so is found naturally in uranium ores.

After it's invention by Marie Curie in 1898, it became a popular subject in common talk, because radioactivity was a knew advance in science and wasn't known to be particularly dangerous at the time.

Radium was also the subject of many rumors, people thought radium-powered reactors could power humanity for the rest of time(which it can't), and radium was also thought to be a "health" product, being added to drinking water, facial products, and many other things, because radioactivity was thought to cure cancer due to it killing only reproducing cells, which cancer cells do much faster than normal ones, however this is wrong, and the harm inflicted on healthy cells makes you far more likely to get cancer in the first place.

There where several valid uses of radium, one being in a glow-in-the-dark paint, which was a mix of a radium compound and a phosphor which glowed when excited by radioactivity. This paint was heavily applied to watch hands and faces, other dials, switches, the military especially used it heavily on airplane gauges and controls. This paint would glow for about 40 years strait, no matter the conditions, and when it stopped glowing, it wasn't due to the decay of the radium, but to the shattering of crystals in the phosphor. Most times the phosphor can be re-applied and work just as well, even 50 years after it was originally made.

Radium lost popularity when under-aged female workers who painted watch hands and faces with radium paint contracted severe bone cancer from ingesting small amounts of radium. Because radium is chemically is similar to calcium, the body places it into bones, where it's radioactivity slowly destroys bone marrow responsible for making new blood cells, along with being weaker than calcium, so making bones extremely frail and prone to breaking.

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