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
8. rare earth elements

Anotations

Scope note:

Rare-earth metallic element having symbol Sc and atomic number 21. Scandium is a soft, silvery-white metal which does not tarnish in air. It was discovered in 1879 but predicted a decade earlier and given its initial name, ekaboron.