Epidote

Epidote

Plutonic Rocks

Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019

Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough

Secondary minerals are common in plutonic rocks of all kinds. How do they form and what characteristics might you see that help you identify them as secondary? Epidote is a common secondary mineral in granite and some other felsic rocks. Serpentine, talc, and chlorite are common secondary minerals in mafic rocks. Why the difference? Why are the most common secondary minerals in felsic and mafic rocks different?

Cretaceous molybdenite in metasomatic epidosite associated with the Pounamu ophiolite, New Zealand

View Article

Journal Information

Published in New Zealand Journal of Geology and Geophysics, 2020

Alan F. Cooper, Anthony Reay, Trevor R. Ireland, Marc D. Norman

Epidosites are dominated by the mineral epidote, Ca2(Al,Fe)3Si3O12(OH), a solid solution series with Al-end member clinozoisite (Cz) and Fe-end member pistacite (Ps). When the epidosite compositions are recalculated to an epidote mineral formula they correspond to a narrow range from Ps19.2 Cz80.8 (OU46254) to Ps17.7Cz82.3 (OU46247), with slight stoichiometric excess of Si, reflecting the presence of quartz in the mineral assemblage.

Explore chapters and articles related to this topic

Plutonic Rocks

Cretaceous molybdenite in metasomatic epidosite associated with the Pounamu ophiolite, New Zealand