1. coarse-grained igneous rocks formed from the final stages of magma crystallization, typically containing large crystals and rare minerals
Usage: geological

Examples

• The geologist discovered valuable minerals in the pegmatites near the granite outcrop.
• Pegmatites often contain gemstones like tourmaline and beryl.
• The mining company extracted lithium from pegmatites in the region.
• These pegmatites formed when the last remnants of magma cooled slowly underground.
• The museum displayed specimens of pegmatites showing exceptionally large feldspar crystals.
• Rare earth elements are sometimes found concentrated in certain pegmatites.