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. chalk

Anotations

Scope note:

Drawing medium made from natural red clay containing iron ocher, ranging in color from reddish brown to blood red. It was used for wall paintings by ancient Egyptians and Romans; in the 16th century it was a popular drawing medium. Originally cut from deposits but later fabricated from the same material.