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. mineral

Additional parents:

1. top of the aat hierarchies
2. Materials Facet
3. Materials
4. materials
5. materials by composition
6. inorganic material
7. rock
8. rock by form
9. stone
10. stone by quality
11. gemstone
12. gemstones by specific type

Anotations

Scope note:

A mineral with the same composition as pyrite (fool's gold) but differing in crystal structure. It can be faceted like a gemstone; it was popular in the 1920s to 1930s, usually set in sterling silver. It is commonly found as nodules and concretions in sedimentary rocks.