Rimfire Pacific Mining N L’s latest drilling program at its wholly-owned Valley Project has intersected prospective copper porphyry-style host rocks, analogous to other significant producing mines in the New South Wales’ prolific Lachlan Fold Belt.
Recently, the gold and copper explorer set out to drill one deep and one shallow diamond hole at the base metals play, testing two separate targets — one of which is magnetic.
Rimfire intersected the magnetic target at around 350 metres vertical depth and, while assay samples were only collected from various downhole zones of the deep diamond hole, the results included 26 metres at 410 parts per million copper downhole from 96 metres, including 10 metres at 800 parts per million from 97 metres downhole.
Moving forward, Rimfire intends to conduct further drilling over its 100%-owned project’s magnetic features and to test a number of surface geochemical and alteration zones with aircore exploration.
“Encouraging recent results”
Rimfire Pacific managing director Craig Riley said: “These encouraging recent results demonstrate that the Valley Project has many characteristics that are supportive of hosting a potentially significant porphyry copper source in a similar setting to that observed at the Northparkes and Cadia mines.
“The company is excited about undertaking the next round of deeper drilling at the Valley Project to better vector to areas of mineralisation.”
Rimfire’s Valley Project is one of four key project areas the gold and copper explorer is developing along New South Wales’ prominent Lachlan Fold Belt.
The Fifield and Avondale projects are being explored under joint venture agreements, while the Valley and Cowal projects are 100%-owned by the ASX-lister.
Deep diamond hole results
To further explore copper targets at the Valley Project, Rimfire set out to drill two diamond holes, reaching 463 metres and 151 metres in depth, respectively.
The holes set out to test two targets:
- A deeper magnetic target, interpreted as Ordovician volcanics that are related to porphyry-style mineralisation in the region; and
- The source of surface geochemical anomalism along a ferruginous ridge and an induced polarisation geophysical feature in the vicinity.
In the deep diamond hole, which returned assays from intervals starting from 75 metres to end-of-hole, Rimfire encountered a strong propylitic epidote-chlorite altered volcanoclastic unit. Diamond core drilling at the Valley also intersected a zone of steeply dipping (near vertical) fault breccia stringers
Identified at around 350 metres deep, the target was interpreted as a Raggatt Volcanics sequence, which is equivalent to host rocks at the Northparkes copper-gold mine.
Interestingly, reprocessed magnetic data highlights a cluster of interpreted intrusive rock bodies adjacent to recent drilling, which are high priority porphyry-style copper-gold drill targets analogous to the Northparkes mine.
Looking ahead, assays for the shallow diamond hole drilled at The Valley are pending and anticipated next month.
Owing to the fact the Valley Project was largely unexplored until last year, Rimfire believes the latest diamond drilling assays are “very encouraging” and bode well for the next phase of the company’s exploration program.
Next steps
Moving forward, Rimfire will drill magnetic features that could lead to a cluster of porphyry intrusive centres, consisting of magnetic lows and highs with marginal zones that could host mineralisation.
Six deep diamond drill holes with RC pre-collars, covering roughly 3,000 metres, are planned to test these zones.
Rimfire also intends to test a number of surface geochemical and alteration zones across the project area with focused aircore drilling. All up, 100 aircore holes, for around 1,500 metres, are planned to test these areas of interest.