Allotropes are different chemical structures resulting from the same element.
A major example is the differing allotropes of carbon:

  • Diamond - Covalent Network creating a lattice
  • Graphite - A series of lattice sheets which are connected only through weak sea of delocalised electrons between the sheets. This gives graphite two properties:
    • Use as a lubricant.
    • A conductor or because it has low conductance compared to metal, slight resistance.
  • C60 - Buckminsterfullerene, a ball of carbon with very strong covalent network bonds. The balls are very strong structurally but have very low