Thor Mining PLC (ASX:AIM:THR) Off-hole Electromagnetic Conductor identified beneath Nickel Gossan

The directors of Thor Mining Plc (“Thor”) (AIM, ASX: THR, OTCQB: THORF) are pleased to announce that anomalous nickel assays results from RC drilling have been returned and that an off-hole conductive anomaly has been identified from a subsequent down-hole electromagnetic geophysics survey at the Krona Prospect, within the Company’s 100% owned Ragged Range Project, located in the Eastern Pilbara, Western Australia.

Project highlights:

· The shallow conductor, identified from the recent high-powered Fixed Loop Electromagnetics (FLEM) ground geophysics survey beneath the nickel gossan at the Krona Prospect, was drill tested with one RC drill hole, returning:

o 22RRRC045: 66m @ 0.19% nickel from 81m

· The drill hole intersected the edge of the modelled FLEM conductor.

· A down-hole electromagnetic (DHEM) geophysics survey was completed and revealed an off-hole conductor consistent with sulphides and warrants drill testing to validate.

· The nickel gossan is located at the basal contact of the Dalton Suite ultramafic unit (altered Archean Komatiite) in the classic location for nickel-copper sulphide mineralisation.

22RRRC045 looking NE

Nicole Galloway Warland, Managing Director of Thor Mining, commented:

“I am encouraged that the down-hole geophysics survey at the Krona Prospect, Ragged Range has identified an off-hole electromagnetic conductor, and that the target is genuinely anomalous for nickel with assay values above background lithological values. This result warrants further drill testing to confirm this understanding.

“We are currently designing a drilling program at the Kelly’s Prospect following up the high-grade gold in rock chips.”

Next Steps

  • Samples have been submitted for assay of Platinum Group Elements (PGEs).
  • Design follow-up drill holes to target the DHEM conductor.
  • Awaiting drill assay from the recent Sterling Prospect RC drilling program.
  • Commence the RC drilling program at the Kelly’s Prospect, following up on high-grade gold in rock chips (up to 15.5g/t Au) (RNS: THR announcement 25 July 2022).

The Ragged Range Project, located in the prospective Eastern Pilbara Craton, Western Australia, is 100% owned by Thor Mining (covering E46/1190, E46/1262, E46/1355, E46/1340 and recently granted E46/1393 (Figure 1)).

Figure 1: Tenement location map showing the gossan position, Krona Prospect adjacent to Sterling Prospects 13km gold trend

Krona Prospect – Nickel Gossan

One RC drill hole of 174m was drilled to test the shallow (100m) conductor identified by the high-powered Fixed Loop Electromagnetics (FLEM) ground geophysics survey completed in June 2022 at the Krona Prospect. Due to the steep slopes around the gossan, the closest achievable collar position was around 50m from the SE corner of the plate and 130m from the plate’s centre.

An intersection of 66m @ 0.19% Nickel from 81m was returned in 22RRRC045. Whilst the hole intersected the modelled EM plate, it did not intersect massive or disseminated sulphides. It did however intersect a graphitic shale from 60-72m down hole, but this did not explain the source of the conductor as it was too shallow (~50m above the modelled plate).

Figure 2: FLEM survey showing EM conductor and location of RC drill hole overlain on the 100K GSWA Geology.

To resolve the source of the conductor, the hole was cased and a down-hole electromagnetic (DHEM) survey was completed by Vortex Geophysics. This used a small 100m x 150m loop, oriented to couple both with flat lying conductors, below the loop, and steeply dipping conductors in the vicinity of the graphitic zone at ~70m down hole. The layout is shown in Figure 3.

Figure 3: EM conductor identified by FLEM survey and location of RC drill hole trace overlain on the airphoto.

The DHEM identified a clear off-hole conductor at around 85m down hole, with a modelled response of -42° dip towards 312° azimuth and has a plunge of 14° to the NE but appears to flatten in places. The plunge is not well constrained and could be traded off against a small shift in the modelled plate along strike.

The modelled plate and the down hole response for channel 11 (1.8695 m Sec) are shown in Figure 4. If the modelled plate is extrapolated up dip it intersects the hole at a depth of around 30m, not at the graphitic intersection at ~70m as one might expect if that was the source of the conductor. The tenor of the EM response does not suggest a massive nickel sulphide source or even a strong conductor, but it may be networked sulphides which warrants a drill hole to test it. The local geological regime is interpreted to be a broad NE trending fault zone (Figure 5) with the Krona gossan sitting above its hanging wall and the modelled plate and graphite zone sitting closer to its footwall.

Figure 4: View from WNW showing the measured DHEM Ch11 response, FLEM modelled plate (red) and DHEM modelled plate (black).

Figure 5: Plan view of the interpreted DHEM plate (yellow), gossan outline (purple), DHEM loop and FLEM lines (blue), drill hole and contours of Ch21 total field magnitude from the FLEM overlain on a greyscale image of the AGC of the TMI.

Downhole Geochemistry

Lab assay data from sampling of 22RRRC045 was analysed in ioGAS software. This verified that there were anomalous nickel assays above the background range naturally expected in an ultramafic lithology. In addition, the Fe vs Ni graph showed that iron was not preferentially scavenging nickel (thus not producing false anomalies), and there were zones of sequential negative correlation downhole as shown in Figure 6.

Figure 6: All assay data from 22RRRC045, showing the anomalous Ni assays above the normal range expected in ultramafic rocks. The sequential negative correlation of Fe and Ni from 51-57m down hole (green dots) and 80-99m down hole (blue dots) are shown, and the red dots are the remainder of the anomalous Ni assays.

By using the ‘real’ nickel anomalies in Figure 6, significant nickel intersections in 22RRRC045 are more accurately reported in Table 1 and Figure 7.

Table 1: Significant intersections from the anomalous nickel zone in Figure 6

Hole ID


From depth (m)

To Depth (M)

Interval (m)

Nickel (Ni) %

























Figure 7: Down-hole assay data from 22RRRC045, showing the anomalous Ni assays in relation to the same red, green, blue and black dots from Figure 6.

Table B – RC Drill hole collar details

Hole ID





Azi (True N)

Depth (m)









· Bagas et al., 2004. Geology of the Spilt Roc 1:100,000 Sheet. 1:00,000 Geological Series. Geological Survey of Western Australia

This announcement is authorised for release to the market by the Board of Directors.

For further information, please contact:

Thor Mining PLC

Nicole Galloway Warland, Managing Director

Ray Ridge, CFO / Company Secretary

Tel: +61 (8) 7324 1935

Tel: +61 (8) 7324 1935

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