pegmatite
noun/ˈpɛɡmətaɪt/
Etymology From Ancient Greek πήγνυμι (pḗgnumi, “to attach, join”) + -ite
1
A coarsely crystalline igneous or plutonic rock composed primarily of feldspar and quartz, normally with muscovite and/or biotite mica.
- Derived terms
- micropegmatite, pegmatitic, pegmatize, pegmatoid