Castillo Copper Ltd (ASX:CCZ) intends to fast-track reverse circulation (RC) drilling campaigns at the priority Arya prospect and Big One deposit targets at Mt Oxide pillar in Queensland’s Mt Isa copper-belt.
Arya is prospective for IOCG mineralisation and comprises a sizeable massive sulphide bedrock conductor while Big One comprises shallow high-grade supergene copper ore.
The company is preparing applications for drilling approvals to be presented to Queensland's resources regulator.
Managing director Simon Paull said: “Based on the underlying fundamentals of the prospects reviewed to date, the board has decided to expedite drilling the Arya prospect and Big One deposit.
“With drill-test targets selected and most preliminary work complete, we anticipate drilling commencing once Queensland’s resources regulator grants approval.”
Arya was initially discovered via geophysics work in 1997 by BHP and again by Geoscience Australia in 2019.
The prospect was determined to be a sizeable massive sulphide bedrock conductor after assayed rock chips at surface, up to 1.84% copper (grade four), were interpreted as up-dip extensions to the main sulphide body that correlated with the bedrock conductor.
BHP noted Arya was prospective for IOCG mineralisation and recommended follow-up drilling, however, this never materialised likely due to a base metals downturn in the late 1990s.
Surface assays and AEM anomaly at the Arya Prospect
Big One deposit
The Big One was RC drilled in 1993 by West Australian Metals with 27 drill-holes for 1,673 metres and had excellent economic intercepts up to 28.4% copper (grade five).
Notably, the drilling intersected shallow high-grade supergene copper ore.
In 1997, around 4,400 tonnes of supergene ore was mined from the deposit within historic mining lease ML5481 that delivered an average 3.5% copper (grade six).
Priority targets finalised
Priority targets to test-drill at Arya and Big One have been finalised and drilling contractors are being invited to submit quotes to run the twin RC drilling campaigns.
Earlier work has already ensured most of the necessary landholder and accessibility agreements are in place.
In addition, a contractor has been selected to clear access tracks, which were adversely affected following the wet season and severe cyclone that hit the Gulf of Carpentaria.
An application to progress the drilling campaigns will shortly be filed with Queensland’s resources regulator and, once approval is secured, then the drilling teams will be fast-tracked to site.
The next steps are to ensure all the necessary logistics are in place and following up with stakeholders to ensure key approvals are secured.
Mt Oxide is one of three pillars the company is pursuing as part of plans to become a mid-tier copper producer.