Garfield Project

The Garfield Prospect is hosted by MRV-Western Sequence felsic volcaniclastics and volcanics grading into epiclastic sediments in the west. The contact between the western sequence and the Tyndall Group is to the west of the prospect area and is probably a faulted contact. A porphyritic andesite is present within the package and is thought to be a sub-volcanic intrusive. This has undergone extensive hydrothermal alteration and has copper-gold mineralisation associated with it. The enclosing felsic volcanic rocks are also extensively hydrothermally altered. A series of North-East trending faults dissects and offsets the andesite unit.

Copper-gold mineralisation is present as open stockworks and disseminations of chalcopyrite associated with a more intense pyritic alteration facies within the porphyritic andesite.

Mineralisation is accompanied by intense chlorite-pyrite-carbonate alteration, with a magnetite-apatite-fluorite association seen in parts of the mineralised body, possibly suggesting two episodes of mineralisation. Isotope studies conducted in the mid 1990’s suggest the Garfield mineralisation to be an analogue to the mineralisation seen at Mt Lyell.

The Garfield Prospect was first discovered as recently as 1994 by Renison Goldfields Consolidated (RGC being the operator of the Mt Lyell Mine at the time). Geological mapping found extensive alteration within the porphyritic andesite and the first drill hole GAR001 was collared to test the alteration zone (see table for all significant drilling intercepts at Garfield) and intersected 144m @ 0.25% Cu, 0.05 g/t Au associated with pyrite-chlorite-magnetite alteration, with some apatite and fluorite associated with the magnetite.

Induced Polarisation (IP) and Ground Magnetic surveys were undertaken to target the mineralisation and a further 13 drill holes were completed. A review of the geophysics and drill hole targeting by Corona Staff has indicated that the drill hole locations recommended by the RGC geophysicists were not drilled; therefore the IP and magnetic anomalies may not have been properly tested. Newcrest drilled one 700m hole south of the main mineralisation in 2005 to test for mineralisation south of a known fault within the andesite. No significant assays were returned, although some confusion with geophysical interpretation was noted.

No petrographic or mineragraphic studies were conducted on the Garfield mineralisation by RGC.

Corona has reviewed the RGC geophysics, utilising modern software to generate more accurate models. Preliminary results indicate that RGC didn’t test all the geophysical anomalies, and previous interpretations were inaccurate meaning some of the anomalies were not covered by drilling.