Soda lite syenite: Like granites, syenites can be divided into those in which the feldspars are mainly potash (potassium) or soda (sodium). Sodalite syenites such as pulaskite and nordmarkite are often perthitic, which means the sodium feldspar, mainly albite. intergrows with potash feldspar and gradually replaces it. Sodalite syenite can often be identified by lavender-blue specks of the feldspathoid sodalite.