Nepheline syenite
| Igneous rock | |
Hand samples of nepheline syenite of the Ordovician Beemerville Complex, northern New Jersey | |
| Composition | |
|---|---|
| Primary | alkali feldspar, nepheline, clinopyroxene, amphibole, biotite |
| Secondary | magnetite, ilmenite, apatite, titanite |
Nepheline syenite is a holocrystalline plutonic rock that consists largely of nepheline and alkali feldspar. The rocks are mostly pale colored, grey or pink, and in general appearance they are not unlike granites, but dark green varieties are also known. Phonolite is the fine-grained extrusive equivalent.