Structure of the article
  1. Infobox
  2. Lede
  3. Characteristics
    1. Physical
    2. Allotropy
    3. Isotopes
  4. Occurrence
    1. Geological
    2. Biological
  5. History
  6. Production
  7. Chemistry and compounds
    1. Brief comparison with group members
    2. Common oxidation states
    3. Discussion of inorganic (halide, chalcogenide), and organometallic (metallocene) compounds as appropriate
  8. Applications
  9. Biological significance (if appropriate; consider merging with "biological occurrence")
  10. Precautions
  11. References
  12. External links
  13. Navboxes (as appropriate)