A Corundum-Quartz Assemblage in Altered Volcanic Rocks, Bond Range, Tasmania

R. S. Bottrill
Mineral Resources Tasmania, P.O. Box 56, Rosny Park, Tasmania, Australia

Abstract: Unusual corundum-bearing rocks occur in the Bond Range, northern Tasmania, in a hydrothermally altered Cambrian quartz porphyry. The assemblage exhibits quartz and corundum in mutual contact, a rare phenomenon, in association with andalusite, pyrophyllite, diaspore and other minerals. This metastable assemblage apparently resulted from advanced argillic alteration at moderate temperature and low pressure, followed by rapid depressurisation accompanying boiling of hydrothermal, granite-derived fluids. This corundum occurrence appears to be unrelated to the sapphires in placer deposits in Tasmania.

Keywords: Corundum • quartz • diaspore • pyrophyllite • andalusite • Tasmania • advanced argillic alteration

Mineralogical Magazine; June 1998 v. 62; no. 3; p. 325-332; DOI: 10.1180/002646198547710
© 1998, The Mineralogical Society
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