Castillo Copper Ltd (ASX:CCZ) has unearthed significant shallow clay-hosted rare earth elements (REE) at the Broken Hill Alliance (BHA) Project’s East Zone in Far West New South Wales, with assays returning up to 2,410 parts per million (ppm) total rare earth oxides (TREO), with up to 29.9% magnet REOs.
The discovery has prompted the company to shift its strategic focus to the REE mineralisation across the East Zone in light of the growing global demand for rare earth metals.
The best intercepts from seven drill holes across the Fence Gossan (FG) and Tors Tank (TT) prospects include:
- 20 metres at 1,780 ppm TREO (28.9% magnet REO) from surface, including 4 metres at 2,410 ppm TREO from 16 metres, and 32 metres at 636 ppm TREO (25.7% magnet REO) from 52 metres in hole FG_003RC at FG;
- 7 metres at 1,048 ppm TREO (29.9% magnet REO) from 12 metres at TT;
- 19 metres at 847 ppm TREO (29.6% magnet REO) from surface at TT;
- 8 metres at 773 ppm TREO (24% magnet REO) from 48 metres, and 28 metres at 614ppm TREO (27.8% magnet REO) from 4 metres at FG;
- 4 metres at 732 ppm TREO (27.1% magnet REO) from 24 metres at TT; and
- 19 metres at 661 ppm TREO (28% magnet REO) from surface at FG.
Six out of the seven holes also intersected cobalt mineralisation above 150 ppm, which was in line with expectations.
With REE mineralisation open in all directions, and FG about 4 kilometres long by 1-kilometre-wide, Castillo will follow up with geological mapping, sampling and auger drilling to extend the known strike event to the west and identify new targets for drill testing.
Tors Tank TT_005DD core showing clay and fresh pegmatites.
"Game-changing" discovery
“With global demand for REEs on an upward trajectory, the board is delighted the assays confirm a new shallow clay-hosted REE discovery within the BHA Project’s East Zone," Castillo Copper’s chairman Ged Hall said.
“In particular, the board notes drill-hole FG_003RC, which intersected an aggregate 52 metres of REE mineralisation.
"This is a game-changing event for the group, as exploration efforts moving forward are going to focus on extending known REE mineralisation, especially at the Fence Gossan and Iron Blow prospects in due course.”
Fence Gossan – key focus to extend known REE mineralisation.
Iron Blow Prospect
The REE assays for FG and TT also confirmed a geological nexus to the Iron Blow Prospect, about 15 kilometres northwest.
This is based on recent re-assays of diamond core from drill-hole DD90_IB3, which intersected fresh pegmatite cumulatively hosting REE mineralisation over 35 metres.
Among the best intersections were 8 metres at 1,460 ppm TREO from 150 metres and 12 metres at 297 ppm TREO from 199 metres.
Further core has been cut and sent to the laboratory to determine if there is shallower REE mineralisation, which will build the case to identify and drill-test priority targets.
Cutting core from TT_005DD.