The Heavy Minerals of the Plutonic Rocks of the Channel Islands: 1. Jersey

Abstract

The following investigation was undertaken not only with a general descriptive aim, but also to endeavour to ascertain how far correlation of isolated plutonic outcrops can be made by means of the study of the accessory minerals. It is in addition an attempt to supply further evidence bearing on the relative ages of the Jersey granites and diorites in view of the opinion of Dr. G. H. Plymen, based on field evidence, that the granites are of two ages, but both Pre-Cambrian, the Mont Orgueil and Gorey granite being the older.