[gran-uh-fahyuh
r] 
| a fine-grained or porphyritic granitic rock with a micrographic intergrowth of the minerals of the groundmass. |
| gran·o·phyre (grān'ə-fīr') n. A fine-grained granite porphyry having a groundmass with irregular intergrowths of quartz and feldspar. [German Granophyr : grano-, grano- + (Por)phyr, porphyry (from Medieval Latin porphyrium; see porphyry).] gran'o·phyr'ic (-fîr'ĭk) adj. |
| granophyre (grān'ə-fīr') Pronunciation Key
A fine-grained igneous rock that has large intergrown crystals of quartz and feldspar in the matrix. |
granophyre
fine-grained igneous rock that is characterized by a porphyritic texture, having large crystals (phenocrysts) that rest in a nonglassy, finely crystalline matrix (groundmass). Granophyre is similar to granite, except for its fine texture and smaller grain size; those granophyres that have quartz and alkali feldspar phenocrysts in a groundmass of quartz, alkali feldspar, and mafic (dark-coloured) minerals resemble rhyolite, while others consist of micropegmatite (q.v.).
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