Junior explorer Carawine Resources (ASX: CWX) has reported “compelling new evidence” for a copper-gold porphyry source of mineralisation at the Hill 800 deposit within its Jamieson project in northeast Victoria.
The company said an analysis of multi-element geochemical data by industry expert Dr Scott Halley provides strong geochemical evidence that a copper-gold porphyry intrusion may be the source of mineralisation at the deposit.
Dr Halley is recognised as an expert in the field of geochemistry and has consulted to more than 100 mining and exploration companies in over 25 countries.
His findings follow the recognition in July of two distinct magnetic anomalies from regional-scale survey data at Jamieson.
Magnetic anomalies are commonly associated with mineralised porphyries and can be ideal targets for drill testing.
Hill 800 is the most advanced prospect at Jamieson, with drilling to date returning outstanding widths and grades of gold and copper mineralisation from intensely altered volcanics.
Managing director David Boyd said the new information was an “exciting development” for Carawine, and could lead to a major new discovery in the region.
“Earlier this year we established a new interpretation for Hill 800, demonstrating the potential for high-grade mineralisation to continue at depth beneath the current limit of drilling,” he said.
“These latest results suggest a fertile copper-gold porphyry is driving the mineral system [and] gives us confidence that we could be chasing a porphyry copper-gold target at depth beneath Hill 800, and potentially at Rhyolite Creek as well.”
Rhyolite Creek is located 5 kilometres to the south of Hill 800 and comprises three targets for follow-up drilling – two potential large-tonnage, lower-grade gold and copper targets; and one seafloor position VHMS, high-grade gold and base-metal target.
At surface, the prospect is defined by an extensive gold and copper soil anomaly in rhyolitic rocks and as with Hill 800, sits directly above a significant regionally anomalous magnetic high.
Porphyry deposits are attractive targets for exploration companies as they are typically very large systems with economic concentrations of copper and gold, multiple deposits and strong grade characteristics.
Australian examples include the Cadia Valley (owned by Newcrest Mining, ASX: NCM) and Northparkes (CMOC) operations in New South Wales.
A key targeting feature for copper-gold porphyry deposits is the biotite-magnetite alteration associated with the potassic zone, which commonly appears as an anomaly in geophysical survey data.
Mr Boyd said work would now commence on an exploration program to define the geometry and depth of porphyry targets within Jamieson, to enable drilling later this year following the release of a maiden mineral resource for Hill 800.
At mid-afternoon, shares in Carawine Resources were up 24.14% to $0.180.