Chromium

EnvironmentalChemistry.com: Chromium - Atomic structure, chemical and physical properties, and table of nuclides.
http://environmentalchemistry.com/yogi/periodic/Cr.html

USGS Minerals Information: Chromium - Statistics and information on the worldwide supply, demand, and flow of the element (PDF format).
http://minerals.usgs.gov/minerals/pubs/commodity/chromium/

ChemGlobe: Chromium - Electronic, thermal, and steric data along with an isotopes table.
http://partisans.spurious.biz/~pkremer/projects/chemglobe/ptoe/_/24.html

Lenntech: Chromium - Physical data, chemical properties, health and environmental effects.
http://www.lenntech.com/Periodic-chart-elements/Cr-en.htm

Visual Elements: Chromium - General and physical information, source, uses, key isotopes, and ionisation energies.
http://www.chemsoc.org/viselements/pages/chromium.html

It's Elemental: Chromium - Basic physical and historical information.
http://education.jlab.org/itselemental/ele024.html

Wikipedia: Chromium - Properties of the element, including its history, applications, and characteristics.
http://en.wikipedia.org/wiki/Chromium

Radiochemistry of Chromium - Full text of the monograph by J. Pijck (Laboratory for Analytical Chemistry, University of Ghent, Ghent, Belgium). [PDF] <small>(December, 1964)</small>
http://library.lanl.gov/cgi-bin/getfile?rc000002.pdf

LANL: Chromium - History, sources, uses, and compounds.
http://periodic.lanl.gov/elements/24.html

WebElements: Chromium - Extensive information on history, uses, occurrence, compounds, and properties of the element.
http://www.webelements.com/webelements/elements/text/Cr/key.html

ChemicalElements.com: Chromium - Basic information, atomic structure, and isotopes.
http://www.chemicalelements.com/elements/cr.html