21. Sahand is made chiefly of dacite and associated felsic rocks. 22. The ore deposits reside in veins present in the dacite volcanic dome. 23. About of dacite erupted in Garibaldi's third period of activity. 24. Rocks of dacite composition show that within magma chambers frational crystallization occurred. 25. The volcanic cones are composed of andesite, basaltic andesite and dacite . 26. Granodiorite is felsic to intrusive igneous equivalent of the extrusive igneous dacite . 27. The north east of the suburb has dacite from the Canberra Formation. 28. Dykes have outcrops of trachytic andesite, dacite and rhyodacite. 29. Andesites contain quartz and dacites -rhyodacites contain sanidine megacrysts. 30. Guallatiri has erupted andesite, dacite and rhyolite, with dacite dominating.
