Radium
Links
Radiochemistry of Radium
http://lib-www.lanl.gov/cgi-bin/getfile?rc000041.pdf
Full text of the monograph by Murrell L. Salutsky (W.R. Grace & Co., Research Division, Washington Research Center, Clarksville, Maryland) and H. W. Kirby (Mound Laboratory, Miamisburg, Ohio). [PDF]
It's Elemental: Radium
http://education.jlab.org/itselemental/ele088.html
Basic physical and historical information.
ChemicalElements.com: Radium
http://www.chemicalelements.com/elements/ra.html
Basic information, atomic structure, and isotopes.
Visual Elements: Radium
http://www.chemsoc.org/viselements/pages/radium.html
Image, general and physical information, source, uses, key isotopes, and ionisation energies.
EnvironmentalChemistry.com: Radium
http://environmentalchemistry.com/yogi/periodic/Ra.html
Atomic structure, chemical and physical properties, and table of nuclides.
WebElements: Radium
http://www.webelements.com/webelements/elements/text/Ra/key.html
Extensive information on history, uses, occurrence, compounds, and properties.
Lenntech: Radium
http://www.lenntech.com/Periodic-chart-elements/Ra-en.htm
Physical data, chemical properties, health and environmental effects.
Wikipedia: Radium
http://en.wikipedia.org/wiki/Radium
Properties of the element, including its history, applications, and charateristics.