Boron
Comprehensive historical data about the element and its compounds.
BoronWeb
Boron chemistry and links to boron chemists around the world.
ChemicalElements.com: Boron
Basic information, atomic structure, and table of isotopes.
EnvironmentalChemistry.com: Boron
Atomic structure, chemical and physical properties, and table of nuclides.
It's Elemental: Boron
Basic physical and historical information.
Lenntech: Boron
Physical data, chemical properties, health and environmental effects.
USGS Minerals Information: Boron
Statistics and information on the worldwide supply, demand, and flow of the element (PDF format).
Visual Elements: Boron
Image, animation, source, uses, physical information, and covalent bonds.
WebElements: Boron
Extensive information on history, uses, occurrence, compounds, and properties of the element.
Wikipedia: Boron
Properties of the element, including its history, applications, and characteristics.