Skip to main content

Castillo Copper announces new BHA geological report

Published by , Editor
Global Mining Review,

Castillo Copper Ltd’s Board has received a fresh geological report on the Broken Hill Alliance (BHA) Project’s East Zone, which highlights significant exploration potential for cobalt-copper-zinc and possibly lithium mineralisation. A key insight was multiple drill-hole assays which delivered significant cobalt readings. Consequently, with a risk-reward trade-off to the upside from a 100%-owned asset, the Board has decided to focus on developing the BHA Project and dropped plans to pursue the acquisition of the Litchfield and Picasso lithium assets.


  • A review on BHA’s East Zone, acquired from Wyloo Metals in 2020, discovered numerous areas anomalous for cobalt (Co)-copper (Cu) and zinc (Zn) mineralisation delineated from surface/down-hole assays:
    • Notably, with assayed values ranging from >200 ppm Co up to 9500 ppm Co across 108 drill-holes (proximal to the Himalaya Formation out-crop/sub-crop) work on modelling a JORC 2012 compliant mineral resource is now underway.
    • The region is well-known for its cobalt potential, as Cobalt Blue has JORC 2012 compliant ore reserves of 118 million t at 687 ppm Co for 81 100 t contained metal.
  • The Board is highly encouraged by the NSW government’s new strategy, which targets building a viable downstream industry for processing critical minerals (including cobalt-copper-REE’s) and establishing a global supply hub in the state’s central west region.
  • With the BHA East Zone’s exploration potential materially enhanced, the Board has dropped plans to acquire additional lithium assets.
  • Further, the Board will prioritise modelling a JORC 2012 compliant resource at the Big One Deposit and further developing the graphitebase metal discovery at the Arya Prospect.

Castillo Copper’s Managing Director, Simon Paull, commented: “A recent geological review of the Broken Hill Alliance Project’s East Zone uncovered 108 drill-holes yielding cobalt values >200 ppm, with the highest being 9500 ppm. As a result, with the cobalt price now over US$70 000/t on the London Metal Exchange, work on modelling a JORC compliant mineral resource is now underway. Further, surface assays have enabled numerous zones anomalous for cobalt-copper and separately zinc to be delineated that are proximal to the Himalaya Formation out-crop and sub-crop. This is a timely discovery that significantly enhances the project’s exploration potential for battery metals, especially as it coincides with the NSW government launching its critical minerals and high-tech metals strategy. As such, the Board has decided to no longer pursue the acquisition of the Litchfield and Picasso lithium assets.”

Battery metal potential

The review drilled down into all available information to determine the battery mineral potential of the BHA Project’s East Zone (acquired in late 2020 from Wyloo Metals). Pleasingly, analysing assayed surface and down-hole samples enabled numerous zones anomalous for cobalt-copper-zinc mineralisation to be delineated that are proximal with the Himalaya Formation outcrop or sub-crop under shallow (200 ppm Co, with the highest up to 9500 ppm Co. As there are sufficient data points, the geology team are now working on a suitable geological model and estimating a mineral resource to the standard of the JORC 2012 Code.

Within the East Zone, the primary geological target is the Thackaringa style of cobalt mineralisation – this is constrained in or at the margin of the Himalayan Formation. Across the region, there are known cobalt deposits, with COB’s JORC 2012 compliant ore reserve (118 million t at 687 ppm Co for 81 100 t contained metal) arguably one of the largest.

Analysing data for copper in surface rock-chips demonstrates there are several prime anomalous zones, which like cobalt, appear to follow major shear boundaries and trends.

Lithium potential

Within the tenure are numerous zones of pegmatites which have been confirmed through field observations. Furthermore, there is scattered Sundowner Group outcropping which is known to host pegmatites. However, while the pegmatites are prospective for lithium mineralisation, comprehensive sampling work is required to delineate any anomalous areas. To jump start the process, the Board is considering accessing samples from previous drilling – currently retained in the Geological Survey of NSW’s core libraries – and re-assaying for lithium and rare earth elements.

NSW gobernment critical minerals strategy

The Board strongly supports the NSW governments recently launched Critical Minerals and High-Tech Metals Strategy. The core objective is to evolve NSW into a major global supplier and processor of critical minerals and high-tech metals. A key feature is developing significant processing capacity on shore, which is a significant move away from purely exporting raw materials, enabling a high value-adding manufacturing industry to rapidly evolve.

The government intends to take a “coordinated approach across the critical minerals supply chain, supporting the industry from early-stage exploration, through to end uses in manufacturing and recycling.”

This is a major policy shift and could result in a critical minerals hub being established in the state’s central west, which would have significant multiplier benefits for numerous stakeholders (including the BHA Project) along the supply chain. Most significantly, favourable government policy should enhance the central west of NSW as an attractive place for minerals investment.

Option agreement

The Board and companies, which hold the Litchfield and Picasso Lithium Projects, have mutually agreed to unwind the option agreement. As part of the break agreement terms, the AUS$50 000 deposit has been returned to CCZ.

Next steps

In Queensland, the priority is as follows:

  • Assay results for the Arya Prospect.
  • Progress geological modelling and then a JORC 2012 compliant mineral resource for the Big One Deposit.

In New South Wales, the priority is as follows:

  • Commence geological modelling of a JORC 2012 compliant mineral resource for the BHA Project’s East Zone.
  • Formulate surface geophysical surveys then develop inaugural RC drilling campaigns to test priority targets for cobalt-copper-zinc mineralisation.

In Zambia, the priority is to complete the induced polarisation survey for the Mkushi Project and deliver the geophysicist consultant’s review.

Read the article online at:

You might also like

Results come down to training

Martin Engineering highlights the need for regular, thorough training for technicians to ensure safe, efficient maintenance of belt conveyor systems, stressing that well-trained staff and contractors are essential for optimal performance.


Embed article link: (copy the HTML code below):