21. The park consists of three syenite ( a weak form of granite ) mountains. 22. Units within the complex include carbonatite, nepheline syenite , phonolite, and ijolite. 23. The composition ranges from monzonite to quartz syenite . 24. The city has historically developed on seven syenite hills, some of which are high. 25. Extremely iron-rich olivine is rare, but is present in some nepheline syenite . 26. The intrusive members are syenite and carbonatite. 27. He also collected minerals and is noted for his findings of syenite �s a ditroite. 28. In addition to gabbro, the second intrusive suite included nepheline syenite , diorite and monzonite. 29. The mountain is composed of essexite and syenite , strongly contrasting with the surrounding sedimentary rocks. 30. If the rock has a greater percentage of alkali feldspar, it grades into a syenite .
