igneous
Pegmatite
Pegmatite (coarse-grained intrusive igneous rock)
AI-generated identification · may be incorrectHardness varies from 6 to 7 on the Mohs scale, with colors ranging from pink, white, to grey, vitreous to pearly luster, and very large interlocking crystals often exceeding several centimeters.
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Physical properties
Hardness varies from 6 to 7 on the Mohs scale, with colors ranging from pink, white, to grey, vitreous to pearly luster, and very large interlocking crystals often exceeding several centimeters.
Formation & geological history
Formed during the final stages of magma crystallization, where water and other volatiles allow the growth of exceptionally large crystals over millions of years.
Uses & applications
Extracted as a primary source for rare-element minerals, industrial ores such as lithium and tantalum, and specimen collection for gem crystals.
Geological facts
Pegmatites are famous for hosting giant crystals, sometimes spanning many meters, as well as rare gemstone varieties like beryl, tourmaline, and spodumene.
Field identification & locations
Easily identified in the field by its strikingly large mineral grains, particularly massive quartz, feldspar, and mica crystals compared to surrounding host rocks.
