Castillo Copper has delved into historical data for its Mount Oxide project, revealing intercepts of up to 28.4 per cent copper from a supergene ore body.
The review of data for the Big One deposit and Boomerang Mine within the project verifies they are highly prospective priority targets, the company says.
It has described the results as a game-changing development that enhance Mount Oxide’s exploration upside at the same time as a resurgence of interest in the region by large blue-chip groups including Rio Tinto.
“Locating this historic drilling, assay and production data for the Big One Deposit and Boomerang Mine within the 961km2 Mount Oxide pillar, which is in the heart of the Mount Isa copper-belt is a tremendous windfall,” Castillo Copper managing director Simon Paull said.
“As a starting point, our geology team now have ample data points to start formulating a drilling campaign to re-test and potentially expand the known ore body at the Big One deposit, then focus on Boomerang Mine and Arya Prospect. “
The Mount Oxide project is located 150km north of Mount Isa near the old Mount Oxide copper mine.
It is one of three core pillars Castillo is targeting with the aim of becoming a mid-tier copper producer, along with the Cangai copper mine in New South Wales and a package of assets in Zambia.
Wealth of historical information uncovered
Castillo Copper’s geology team had to track down the previous holder of the Big One Deposit mining tenure ( West Australian Metals) to secure the historic information.
During the time period in question there was no legal requirement to lodge drill/assay results as ‘exploration records’ on an existing Queensland Mining Lease, the company said.
Its inquiries brought out a wealth of information including field mapping campaign data sets, information memorandums, faxes and reports with production summaries.
In 1993, West Australian Metals completed a 27-hole RC drilling campaign at the Big One deposit which produced the standout assayed intercept of 3m at 12.25 per cent copper from 42m, with 2m at 17.87 per cent copper from 43m and 1m at 28.40 per cent from 44m. (More HERE)
Notably, in 1997, about 4400 tonnes of supergene ore was mined from the Big One deposit with an average achieved grade of about 3.5 per cent copper. The output was sold to a nearby heap leach operation at Mount Cuthbert.
Historic production records for Boomerang mine from 1944-74 verified that 4211.2 tonnes of oxide ore was mined, grading about 6 per cent copper.
Castillo Copper said more exploration work needed to be undertaken at the site to define the potential scale of the priority targets and the size of any underlying orebodies.