| Lead's lighter carbon group congeners form stable or metastable allotropes with the tetrahedrally coordinated and covalently bonded diamond cubic structure. |
| This qualifier is the general description for the common allotropes of elemental phosphorus. |
| Among different forms of carbon, graphene is one of the widely studied allotropes. |
| The element normally exhibits six allotropes and four oxidation states. |
| Two allotropes of the element exist, accounting for the slight variation in densities. |
| The presence of these many allotropes makes machining plutonium very difficult, as it changes state very readily. |
