Visible copper and zinc minerals have been observed in the core with the drilling at the historical project in northern New South Wales showing potential to expand the resource size.
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With only five holes completed in the 39-hole program, there is significant incremental exploration upside with the company now intending to ramp-up the campaign.
Castillo’s chairman Peter Meagher said: “This is an excellent start to our second drilling campaign.
“Hitting highly mineralised semi-massive and massive sulphides in multiple holes from 41 metres near the start of the drilling program is truly a game-changer, especially with 34 more drill-holes to complete.
“Objective to reopen mine on track”
“This early result materially de-risks the project and firmly places our core strategic objective to re-open Cangai Copper Mine on track.”
In one hole (CC0023R) 18 metres of mineralisation was intersected, including 10 metres of massive sulphides from 41 metres and 2 metres from 56 metres.
The massive sulphides intersected in this hole have extensive visible chalcopyrite, sphalerite, pyrite and pyrrhotite present, which is consistent with historical mine reports.
Massive sulphides from drill hole CC0023R.
Another hole also intersected 18 metres of mineralisation, including 1 metre of massive sulphides from 92 metres and 4 metres of semi-massive sulphides from 110 metres.
There was 8 metres of mineralisation intersected in a third hole, including 3 metres of semi-massive sulphides from 90 metres.
Campaign being expedited
Castillo’s geology team believe the newly found semi-massive and massive sulphides validate that there may be significant incremental mineralisation to be discovered as drilling progresses.
Taking this into account and to build momentum, the company has agreed to the team’s recommendation to expedite the campaign.
A down-hole electromagnetic (DHEM) team is deploying to the site to refine the drilling program’s trajectory.
Drill holes completed along the line of lode at Cangai.
This will enable the geology team to determine potential extensions to newly discovered mineralisation more efficiently.
Due to the campaign being 39 holes, the geology team has some flexibility within the approved program to make refinements if the DHEM team uncover significant new findings.
Diamond rig to be mobilised
A diamond drill rig will be mobilised to the site to undertake critical infill work along the line of lode and aid in expediting the drilling campaign.
The next focus area is a previously identified DHEM anomaly, which is relatively close to where the semi-massive and massive sulphides were intersected.
Once this phase of the campaign is complete, the drill rigs will be moved to the western end of the line of lode.
The company expects to receive initial assay results from the first five holes shortly with ALS in Brisbane fast-tracking this work.
Castillo is focused on reopening the historical Cangai Copper Mine near Grafton in northeast NSW.
The project comprises a volcanogenic massive sulphide ore deposit with one of Australia’s highest grade JORC-compliant inferred resources for copper of 3.2 million tonnes at 3.35%.