Occurrences of zircon in the Dartmoor granite

Abstract

Thin sections afford a very inadequate basis for the determimation of thc accessory minerals present in the Dartmoor granite, and they are of little or no value for assessing the relative proportions of these minerals. A recognizable cryst'd of zircon, for example, is rarely seen iu thin sections of this granite, and uutil zircons were isolated in quantity from the crushed rock, stream-sands, &c., one type of zircon was not detected.