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. rock (inorganic material)
8. igneous rock
9. [igneous rock by composition]
10. [igneous rock by composition: physical]
11. porphyry

Anotations

Scope note:

A rock, similar to diorite, composed of a compact felsitic base in which hornblende or feldspar is porphyritically developed. The celebrated red Egyptian porphyry or 'Rosso Antico' is a red antique porphyry.