Step Out Drilling Confirms High-Grade Cobalt & Associated Copper at Bald Hill

Rimfire Pacific Mining (ASX: RIM, “Rimfire” or “the Company”) is pleased to advise that initial drill assay results have confirmed high-grade cobalt sulphide mineralisation (with strong associated copper anomalism) in the first diamond drill hole completed at the 100% - owned Bald Hill Cobalt Copper Prospect as part of a larger 5 hole (~1,000 metre) step out diamond drilling program.

Highlights

• Hole FI2612 - the first of 5 diamond holes testing cobalt - copper mineralisation at Bald Hill returns high grade cobalt;
  • 29m @ 0.12% cobalt from 66 metres, and
  • 18m @ 0.16% cobalt, 0.16% copper from 110 metres
    including 5m @ 0.21% cobalt, 0.23% copper
• All 5 drill holes have intersected sulphide mineralisation 100- 300m away from the currently defined high-grade cobalt footprint - remaining assays due in 3-4 weeks.
• Rimfire’s drilling to date indicates that Bald Hill hosts some of the highest-grade cobalt mineralisation in the Broken Hill district
• Strong copper anomalism associated with the cobalt upgrades the substantial copper prospectivity at Bald Hill
• South 32 (S32.ASX) and Red Hill Minerals (RHI.ASX) have recently farmed into leases immediately adjoining Rimfire’s project tenements (see Figure 1)

Commenting on the announcement, Rimfire’s Managing Director Mr David Hutton said: “This step-out diamond drill program has substantially expanded the known sulphide hosted mineralised footprint at Rimfire’s 100%-owned Bald Hill cobalt-copper prospect which now extends over a 500m by 200m area.

Assays from hole FI2612 have confirmed that Bald Hill hosts some of the highest cobalt grades in the Broken Hill district. We are encouraged by the presence of copper in these results which highlights the strong potential to find significant copper mineralisation at Bald Hill.

The Rimfire team eagerly awaits assay results from the remaining 4 holes in the program which have all intersected sulphide mineralisation visually similar to that observed in hole FI2612 with results of a similar tenor widely anticipated.

With exciting scandium focused exploration potential also at Rimfire’s Lachlan Orogen assets, the company is eying outstanding upside across our portfolio of critical minerals projects.”

Latest Bald Hill drilling results

Rimfire’s 100% - owned Bald Hill Cobalt Copper Prospect is located approximately 30 kilometres west of Broken Hill, NSW – Figure 1).

Cobalt copper mineralisation at Bald Hill occurs within a folded and faulted sulphide-bearing quartz - albite psammopelitic composite gneiss unit which broadly dips to the east and is underlain by a barren quartz – potassium feldspar gneiss.

Cobalt and copper mineralisation is associated with disseminated to semi massive sulphides (pyrite – pyrrhotite +/- chalcopyrite) that are locally brecciated, and silica altered.

5 diamond holes (FI2612 – FI2616 / 974 metres) were drilled through August and September 2024 to test for extensions of previously drilled high-grade cobalt (Co) mineralisation at Bald Hill, e.g.; 33m @ 0.11% Co from 58 metres in FI2469 including 4m @ 0.23% Co and 2m @ 0.21% Co, and 125m @ 0.13% Co from 198 metres in FI2470 including 97m @ 0.15% Co (see Rimfire’s ASX Announcement dated 8 Augst 2024).

Each of the new drillholes intersected multiple broad zones (downhole widths) of sulphides 100 – 300 metres away from Rimfire’s previous high-grade drill intercepts (see Table 2 for sulphide descriptions) with assay results for the first hole, FI2612 returning (Figures 2 and 3);

• 2m @ 0.37% Cu from 63 metres,
• 29m @ 0.12% Co from 66 metres, and
• 18m @ 0.16% Co, 0.16% Cu from 110 metres including 5m @ 0.21% Co, 0.23% Cu.

The assay results confirm that the sulphides intersected in the drilling are both cobalt and copper- rich and given the similarities between the sulphides interested in FI2612 and the remaining drill holes completed in the program, further drill intercepts of similar tenor are expected.

Significance of the drilling results

The FDI2612 assay results are significant for several reasons as outlined below.

Rimfire’s Bald Hill Prospect represents one of, if not the highest-grade cobalt sulphide occurrence in the Olary and Broken Hill domain (as part of the mineralised Curnamona Province) with other examples typically showing equivalent and significantly lower grades, i.e.; Havilah Resources’ (HAV.ASX) Mutooroo Copper Cobalt Gold Deposit and Cobalt Blue’s (COB.ASX) Broken Hill Cobalt Project respectively (Figure 4).

Click here for the full ASX Release

This article includes content from Rimfire Pacific Mining Limited, licensed for the purpose of publishing on Investing News Australia. This article does not constitute financial product advice. It is your responsibility to perform proper due diligence before acting upon any information provided here. Please refer to our full disclaimer here.