Definitions for "Syenite"
Orig., a rock composed of quartz, hornblende, and feldspar, anciently quarried at Syene, in Upper Egypt, and now called granite.
A granular, crystalline, ingeous rock composed of orthoclase and hornblende, the latter often replaced or accompanied by pyroxene or mica. Syenite sometimes contains nephelite (el├Žolite) or leucite, and is then called nephelite (el├Žolite) syenite or leucite syenite.
A granular, igneous rock composed of orthoclase with or without microcline, plagioclase, hornblende, biotite, and augite. May be considered a granite without quartz.
Keywords:  trachyte, see
see trachyte