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 origin]

Narrower term/s

• dacite [NP]
• rhyolite [NP][+]
  • quartz porphyry [+]
    • elvan
• lava
• pyroclastic rock[+]
  • trass
  • tuff [+]
    • peperino [+]
      • sperone
    • santorin
    • Neapolitan yellow tuff
  • volcanic glass [+]
    • pumice (volcanic rock) [+]
      • tezontle
    • obsidian [+]
      • marekanite
    • perlite
    • tachylite
    • pumice (pigment) [NP]

Anotations

Scope note:

Igneous rock solidified on or near the surface after being ejected explosively or extruded as lava, as contrasted with intrusive rock; characteristically finely crystalline or glassy.