igneous
Mica-rich pegmatite
Granitic pegmatite, likely quartz–feldspar–mica assemblage
AI-generated identification · may be incorrectCoarse, irregular intergrowth of pale quartz/feldspar and shiny dark mica, possibly with light-colored muscovite. Quartz and feldspar are about Mohs 6–7; mica is 2–3, with perfect sheet cleavage; luster ranges from glassy to pearly.
Identified More igneous →
Explore Mica-rich pegmatite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Coarse, irregular intergrowth of pale quartz/feldspar and shiny dark mica, possibly with light-colored muscovite. Quartz and feldspar are about Mohs 6–7; mica is 2–3, with perfect sheet cleavage; luster ranges from glassy to pearly.
Formation & geological history
Likely crystallized slowly from water-rich granitic magma in a pegmatite vein, allowing large crystals to grow. Pegmatites are commonly Precambrian to younger, but this specimen’s age cannot be determined from the image.
Uses & applications
Pegmatite minerals supply feldspar and mica for ceramics, glass, and electrical applications; attractive specimens are collected, and gem-bearing varieties may yield jewelry stones.
Geological facts
Pegmatites can contain unusually large crystals and rare minerals, including tourmaline, beryl, and spodumene.
Field identification & locations
Look for coarse, interlocking crystals and mica flakes that split into thin sheets; common in granitic terrains and veins. The image alone does not establish the exact mineral mix or locality.
