Hierarchy classification:

1. top of the aat hierarchies
2. Materials Facet
3. Materials (hierarchy name)
4. materials (substances)
5. [materials by form]
6. [materials by chemical form]
7. elements (chemical substances)

Anotations

Scope note:

Artificially produced radioactive element in Group VIb of the periodic table, atomic number 106; first created in 1974. Named after the American nuclear chemist Glenn T. Seaborg. It can be created in a laboratory but is not found in nature.