Definitions

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A rock with a porphyritic structure.

from the GNU version of the Collaborative International Dictionary of English

  • n. A rock with a porphyritic structure.

from The Century Dictionary and Cyclopedia

  • n. The name given to those porphyries in which the ground-mass consists chiefly of a triclinic, feldspar, together with either augite or hornblende, or, in some cases, of biotite: in this ground-mass larger crystals of the same species are porphyritically developed.

Etymologies

Sorry, no etymologies found.

Examples

  • Between the quartzite layers are a number of layers of extremely thin mica-porphyrite or shale.

    Wulingyuan Scenic and Historic Interest Area, China

  • Yet here, as we are told by Richthofen and others, there must once have been a great eruptive centre, breaking out again and again, and each time throwing up a different kind of rock: – first Syenite; then Tourmaline granite; then Uralite porphyry; then melaphyr; then, last of all, porphyrite, and the unique Syenite porphyry, famous for its crystals, and unknown elsewhere.

    Untrodden Peaks and Unfrequented Valleys

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