syenite
deep igneous rocks made of alkali feldspar and acidic / intermediate plagioclase, the most common minor constituents are hornblende, biotite, muscovite and accessory are zircon, apatite, sfen; volcanic equivalent: trachyte.
en-GB/saɪɪnaɪt/
deep igneous rocks made of alkali feldspar and acidic / intermediate plagioclase, the most common minor constituents are hornblende, biotite, muscovite and accessory are zircon, apatite, sfen; volcanic equivalent: trachyte.