Castillo Copper (ASX:CCZ) reports assays for 4 drillholes have confirmed potential cobalt, copper-gold and rare earth element (REE) mineralisation at the Fence Gossan Project located within the Broken Hill Project’s East Zone in New South Wales.
The 4 holes that were drilled for 516m intersected a geological sequence comprising clay, amphibolite, schist, gneiss and pegmatite that appear to be dipping moderately.
Similar to findings at the Tors Tank Prospect, the intersected geology is interpreted by the company to be consistent with observations by previous explorers including Broken Hill North during the 1970s and 1980s.
Comparable to the Tors Tank Prospect, the company says there are ‘significant’ magnetite zones that are directly associated with pegmatite up to 19m thick, and these could potentially host REEs and other platinum group elements (PGEs) based on limited pXRF observations.
This interpretation is based on recent re-assays of diamond core from drillhole DD9_IB3 at the Iron Blow Prospect, and the company says it has comparable geology and confirms the presence of ‘high-grade’ REEs within the Broken Hill Project’s East Zone.
Castillo Copper Managing Director Dennis Jensen said, “With the drilling campaign at the halfway mark, the board is optimistic that known mineralisation at the Tors Tank and Fence Gossan prospects has potentially been extended.
“With the drilling campaign at the halfway mark, the board is optimistic that known mineralisation at the Tors Tank and Fence Gossan prospects has potentially been extended”
Moreover, for Fence Gossan in particular, the board is delighted to note the significant pegmatite intercepts which have the potential to host REEs as well as PGEs.”
During the qualitative logging process, Castillo identified multiple disseminated sulphide layers (mostly pyrite) up to 12m thick, and the company says this is ‘significant’ as previous work by Broken Hill North suggested the pyrite hosts cobalt mineralisation.
Further analysis of the samples showed that pyrite is mostly associated with amphibolite layers and ‘thinner, sparser’ horizons which occur and are spread within interbedded schists and gneiss layers.
Castillo says this supports the interpretation that cobalt mineralisation is apparent, but it is subject to final assay confirmation, and field XFR observations indicated positive readings within the amphibolite zones.
The company also observed some pegmatite with some chlorite alteration at intervals throughout drillhole FG_001RC, and very minor epidote alteration and veining was observed at intervals throughout the drillhole.
Minor chlorite and epidote alteration was observed throughout FG_002RC, with trace sulphides observed in a band between 88m to 94m.
Castillo reports FG_003RC intersected schists, pegmatite and 1 amphibolite band containing minor chlorite and epidote alteration observed around 120m to 124m.
It also reports FG_004RC found no pegmatite layers, but did intersect 2 thick bands of amphibolite totaling an apparent thickness of 13m, and minor chlorite and epidote alteration was observed throughout these zones.
Castillo says all reverse circulation (RC) samples have been sent to ALS in Adelaide for further analysis with results expected in a few weeks.
Castillo Copper is an Australian-based explorer focused primarily on copper across Australia and Zambia, and its projects include a ‘large’ footprint in the Mt Isa copper-belt district in northwest Queensland, 4 ‘high-quality’ assets across Zambia’s copper-belt, a ‘large’ tenure footprint near Broken Hill in New South Wales, and the Carnagai Copper Mine in northern New South Wales.
Images: Castillo Copper Ltd