Widespread Secondary Ca Garnet and Other Ca Silicates in the Galway Granite and Its Satellite Plutons Caused by Fluid Movements, Western Ireland

Bernard E. Leake
Department of Earth Sciences, Cardiff University, PO Box 914, Cardiff CF1 3YE

Abstract: Widespread secondary andradite-grossular-hydrogrossular garnet, epidote, prehnite and titanite occur throughout the Galway Granite and its satellite plutons (Roundstone; Inish; Omey and Letterfrack) and even in some of the country rocks several kilometres from the granites. These minerals are not found in low CaO (<1%) granites. They formed as result of secondary fluid movements which altered the biotite, plagioclase and hornblende and also produced sericite and chlorite.

Keywords: andradite • grossular • hydrogrossular • epidote • hornblende • prethnite • Galway • Ireland

Mineralogical Magazine; June 1998 v. 62; no. 3; p. 381-386; DOI: 10.1180/002646198547648
© 1998, The Mineralogical Society
Mineralogical Society (www.minersoc.org)