igneous
Granitic Pegmatite
Pegmatite containing Quartz, Pink Potassium Feldspar, and Muscovite Mica
Hardness: 6-7 (feldspar/quartz); Color: Pink, white, and translucent; Luster: Vitreous to pearly; Crystal structure: Macro-crystalline with large, visible grains; Cleavage: Perfect in one direction for mica and two directions for feldspar.
- Hardness
- 6-7 (feldspar/quartz)
- Color
- Pink, white, and translucent
- Luster
- Vitreous to pearly
Identified More igneous →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 (feldspar/quartz); Color: Pink, white, and translucent; Luster: Vitreous to pearly; Crystal structure: Macro-crystalline with large, visible grains; Cleavage: Perfect in one direction for mica and two directions for feldspar.
Formation & geological history
Formed during the final stages of a magma's crystallization, where high water content allows for the growth of exceptionally large crystals. These often occur in dikes and veins within larger granitic plutons.
Uses & applications
Used as a source for rare earth elements, industrial minerals like quartz and feldspar for ceramics, and as a decorative stone in landscaping or as a collector's specimen.
Geological facts
Pegmatites are famous for containing the largest crystals found on Earth; some crystals have been known to reach lengths of over 10 meters.
Field identification & locations
Identify in the field by looking for very coarse-grained igneous rocks with large pink feldspar crystals and shiny mica flakes. Common in continental shield areas and mountain belts.
