Hierarchy classification:

1. top of the aat hierarchies
2. Materials Facet
3. Materials (hierarchy name)
4. materials (substances)
5. [materials by composition]
6. inorganic material
7. metal
8. [metal by composition or origin]
9. nonferrous metal

Additional parents:

1. top of the aat hierarchies
2. Materials Facet
3. Materials
4. materials
5. materials by form
6. materials by chemical form
7. elements

Anotations

Scope note:

Pure metallic element having symbol TH and atomic number 90; a radioactive, soft, silvery metal most often extracted from the phosphate mineral, monazite. Use also for this metal as processed and formed, usually in combination with other substances, to make various objects and materials.