XRD analysis: drillcore TCDD002, Northern Territory

Abstract

The XRD results generally confirm the presence of most of the minerals indicated by the Hylogger/IR methods, but there are a few significant misidentifications or misses. The Hylogger seems to report hornblende, apatite and hedenbergite/augite incorrectly in some cases; and 'biotite' was actually muscovite. Few major minerals were missed by the Hylogger excepting some minor quartz and feldspar. The aspectral sample was apparently masked by abundant carbonaceous material and pyrite; with the pyrite, muscovite and chlorite not detected by the Hylogger. Garnet was confirmed in two samples but found to be variable, with intermediate compositions between grossularite and andradite, perhaps in zoned crystals. Some muscovite may be phengitic. Chlorite may include some swelling chlorite.