• DDIP modelling has defined a clear geophysical target below and southwest of Oaky Creek South

• The anomaly runs for at least 400m, well beyond the 120m mapped vein footprint

• Up to 32 RC holes are approved, with drilling due in the week beginning July 20

Special Report: Red Mountain Mining has refined a key maiden drill target at Oaky Creek South, with 2D and 3D IP modelling defining a strong chargeability anomaly below and along strike from historical antimony workings.

The anomaly is located below and southwest of outcropping quartz-carbonate-stibnite veins and shallow workings at Oaky Creek South, within Red Mountain’s 100%-owned Armidale antimony-gold project in NSW.

Red Mountain Mining (ASX:RMX) said the DDIP anomaly strikes NNE-SSW, dips steeply to the southeast and shows peak observed chargeability of more than 7.2mV/V against background values of about 2mV/V to 3mV/V.

It runs for at least 400m of strike, well beyond the 120m surface vein footprint at Oaky Creek South, and extends over 100m vertically.

The anomaly strengthens to the south-southwest and remains open, giving Red Mountain a larger untested target ahead of maiden RC drilling.

Red Mountain believes the chargeability response may reflect sulphides in steeply dipping quartz-carbonate-stibnite veins, similar to those mapped and sampled near the old workings.

Reprocessed GSNSW RTP tilt magnetics at Oaky Creek South, highlighting >10ppm Sb auger hits, completed IP lines and key surface geochemical anomalies. Pic: RMX

Drill ready

Red Mountain has contracted Durock Drilling for the maiden RC program at Oaky Creek, with drilling scheduled to start in the week beginning Monday, July 20.

The program has been approved by the NSW Resources Regulator and will include up to 32 RC holes to a maximum depth of 300m.

Initial holes will test mineralisation from surface to 100-150m depth, with approval to 300m giving RMX scope to chase down-dip extensions if early results warrant deeper drilling.

RMX also retains flexibility to shift drill locations based on early results, including along strike or at depth from any mineralised intercepts.

Drilling is expected to wrap up in August, with assays due this quarter.

Four targets

The RC program will test four of five priority orogenic antimony-gold targets outlined by Red Mountain through rock chip, soil and auger sampling over the past year.

These include the Oaky Creek South Main Grid, where a 300m by 30m antimony-arsenic auger soil anomaly has returned rock chips grading up to 39.3% antimony and 1.09ppm gold.

Drilling will also cover the Oaky Creek South Workings, including the newly modelled chargeability anomaly to the south-southwest, plus Oaky Creek North Workings and the antimony-bearing Creek exposure to the north.

The fifth priority target, Oaky Creek North South Extension, is currently under crop and remains inaccessible.

Oaky Creek South 2D resistivity sections showing DDIP lines over key antimony anomalies and workings. Pic: RMX

Bigger system

Oaky Creek is Red Mountain’s most advanced target within the 391km2 Armidale antimony-gold project area.

The prospect hosts quartz-carbonate-stibnite veins and breccias in folded and faulted metasediments, with historical pits and shafts at Oaky Creek North and Oaky Creek South.

Soil, auger and rock chip results point to a potential large-scale orogenic antimony-gold vein system across roughly 3km of surface strike.

Red Mountain said the system is analogous to Larvotto Resources’ Hillgrove project, Australia’s largest known antimony deposit, which sits east of Red Mountain’s project area in the same broader Southern New England Orogen.

The broader Armidale project covers 85km along the western side of the Peel Fault, a major regional structure with more than 400 known orogenic gold and base metal occurrences over 400km of strike.

Despite that endowment, Red Mountain says the fault system remains underexplored, with fewer than 200 mostly shallow drill holes along its length.

First test

Red Mountain prioritised DDIP modelling from its four-line, 6.2 line-km orientation IP survey, given the method’s expected effectiveness in detecting narrow, steeply dipping vein targets like those at Oaky Creek.

Modelling of associated gradient array IP data remains in progress.

Red Mountain said resistivity data from the DDIP survey was broadly consistent with metasedimentary host rocks at Oaky Creek South, though drilling is needed before subtle variations can be confidently interpreted.

The upcoming RC program will provide the first drill test of priority surface and geophysical targets, helping determine if the newly modelled chargeability anomaly reflects chargeable sulphides within antimony-bearing quartz-carbonate-stibnite veins at depth.