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

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

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

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

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

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

Radiochemistry of Chromium
   Full text of the monograph by J. Pijck (Laboratory for Analytical Chemistry, University of Ghent, Ghent, Belgium).
   http://lib-www.lanl.gov/cgi-bin/getfile?rc000002.pdf

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/

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

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