Plutonic Rocks
Preserved but no longer current.
Granites, certain porphyries and other igneous unstratified crystalline rocks, supposed to have been formed at a great depth and pressure, as distinguished from the vol- canic rocks, which were formed near the sur- face. So called by Lyell from Pluto, as the lord of elemental fire.
Era: ca. 1898 (Victorian)
Sources & notes
Reproduced from Brewer’s Dictionary of Phrase and Fable (1898 edition, public domain; archive.org, retrieved 2026-07-31; OCR text, minor errors possible). Reflects the scholarship and attitudes of its era.
Common questions
What does “Plutonic Rocks” mean?
Granites, certain porphyries and other igneous unstratified crystalline rocks, supposed to have been formed at a great depth and pressure, as distinguished from the vol- canic rocks, which were formed near the sur- face. So called by Lyell from Pluto, as the lord of elemental fire.
Is “Plutonic Rocks” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.