Completion of initial drilling program with positive Copper and Gold results
Alford East Copper-Gold ISR Project, South Australia
The directors of Thor Mining Plc (“Thor”) (AIM, ASX: THR, OTCQB: THORF) are pleased to advise copper and gold intercepts significantly above the Mineral Resource Estimate (MRE) cut-off grade, on completion of the initial diamond drilling program at the Alford East Copper-Gold Project, SA.
- Nine diamond drillholes totalling 878m are now complete; with assays from first two drillholes received.
- Significant intercepts including:
21AED001 32.9m @ 0.4% Cu and 0.31g/t Au from 81.5 m, and
5m @ 0.5% Cu and 1.02g/t Au from 102m
21AED002 59.9m @ 0.31% Cu from 21.9m
- Positive correlation between assay results and preliminary pXRF readings for 21AED001 and 21AED002, gives Thor
- greater confidence in pXRF for future drill targeting (AIM: THR Announcement 2930 June 21).
- Significant pXRF copper readings (to be confirmed by laboratory assays) including:
21AED005 73m @ 0.74% Cu from 6.3m (pXRF)21AED004 50m @ 0.45% Cu from 6m (pXRF)
- 21AED002, 21AED006 and 21AED007 were drilled up to 100m to the north of the MRE domain, with assays extending the known copper mineralisation along strike
- Assays from the first two drillholes highlight grade uplift along the north-south trending controlling structure, validating the new geological model and structural controls on mineralisation.
- A water bore was successfully completed for initial ISR pump testing and hydrometallurgical test work.
- Remaining assays expected over the coming weeks.
Nicole Galloway Warland, Managing Director of Thor Mining, commented:
” The new geological model and drill targeting is paying off. The uplift in copper and especially gold grade, adjacent to what appears to be a controlling structure is very exciting and beyond the Directors expectations, suggesting potential for an extended zone of higher-grade copper and gold along this structure.
The intersections of copper mineralisation in three drillholes drilled up to 100m north of the AE-5 MRE, suggests a structural link to the AE-8 domain to the NE, and potentially significant upside to the Mineral Resource Estimate.
These initial copper and gold grades, wide intercepts and increased depth of weathering are all very encouraging for In-Situ Recovery, the innovative mining technique that has minimal impact on the surrounding environment in contrast to conventional open cut mining”.
A copy of the Tenement and Prospect Location Plan may be viewed via the following link:
The Alford East Copper-Gold Project is located on EL6529, where Thor is earning up to 80% interest from unlisted Australian explorer Spencer Metals Pty Ltd, covering portions of EL6255 and EL6529 (ASX: THR Announcement 23 November 2020).
The Alford East Project covers the northern extension the Alford Copper Belt, located on the Yorke Peninsula, SA. The Alford Copper Belt is a semi coherent zone of copper-gold oxide mineralization, within a structurally controlled, north-south corridor consisting of deeply kaolinized and oxidized troughs within metamorphic units on the edge of the Tickera Granite, Gawler Craton, SA.
Utilising historic drillhole information, Thor completed an inferred Mineral Resource Estimate (MRE) (ASX: THR Announcement 27 January 2021):
§ 125.6Mt @ 0.14% Cu containing 177,000t of contained copper
§ 71, 500oz of contained gold
Based on the nature on the oxide mineralisation, the deposit is considered amenable to In Situ Recovery (ISR) techniques.
For further information on ISR please refer to Thor website via this link for an informative video:
Table A: Alford East Mineral Resource Estimate, with AR-5 extending towards AE-8 domains (previously Netherleigh Park) the focus of the current drilling program highlighted.
Note: MRE reported on Oxide material only, at a cut-off grade of 0.05% Copper which is consistent with the assumed In Situ Recovery technique .
A plan view showing the Alford East Project’s eight mineralised domains , may be viewed via the following link:
Alford East Diamond Drilling Program Update
Nine diamond drillholes totalling 878m are now complete, with assays received for the first two drillholes – 21AED001 and 21AED002. This initial program for Thor, focussed only on the northern portion of the Alford East copper-gold deposit around the AE-5 mineralised domains, with drilling targeting areas open at depth and along strike.
Drillhole assay results are reported in Table B and C (Appendices), with significant copper and gold intercepts including:
§ 21AED001 : 108.2m @ 0.17% Cu and 0.1g/t Au from 6.2m, including
25.3m @ 0.11% Cu from 6.2m
32.9m @ 0.4% Cu and 0.31g/t Au from 81.5 m, and
5m @ 0.5% Cu and 1.02g/t Au from 102m
§ 21AED002 : 59.9m @ 0.31% Cu from 21.9m, including
Note for In Situ Recovery Thor is targeting broad copper-gold oxide intervals above the MRE cut-off grade of 0.05% copper.
An Alford East AE-5 Drillhole location plan may be viewed via the following link:
An inhouse Vanta Series C portable X-ray fluorescent (pXRF) analyser was used in the field to take copper readings every 0.5m down each of the holes (gold not measured by pXRF). Preliminary pXRF copper results as reported for 21AED001 and 21AED002 (AIM: THR Announcement 29 June 2021), are almost identical to the assay results, with the assays results slightly higher over some intervals (Table C). This positive correlation gives the Directors of Thor greater confidence with the pXRF readings for future drill targeting.
Preliminary significant pXRF copper readings for all drillholes include:
21AED001 33m @0.4% Cu from 81.5 (previously reported)
21AED002 55.5m @ 0.28% Cu from 28m (previously reported )
21AED003 26m @ 0.1% Cu from 15m
21AED004 50m @ 0.45% Cu from 6m
21AED005 73m @ 0.74% Cu from 6.3m
21AED006 16.5m @ 0.06% Cu from 44.5m
21AED007 29m @ 0.12% Cu from 20.5m
21AED008 5m @ 0.09% Cu from 36.5
21AED009 NSI – No Significant Intersection above 500ppm Copper
Important notice: The pXRF copper readings are indicative only with samples being submitted to laboratory for analytical analysis including gold assay. The Directors believe that with adequate sample preparation the pXRF analyser will yield high-quality analytical data. However, there can be no guarantee that this method provides accurate results similar to those from the laboratory analysis.
Table D: Assay verses pXRF Comparison (pXRF readings and intervals as per THR: AIM Announcement 29 June 2021)
For ISR purposes, drilling was limited to the deeply weathered lithological profile, testing the extent of the oxide zone and the depth boundary of the Top of Fresh Rock (TOFR). The copper-gold oxide mineralisation is hosted within deeply kaolinised (clay) and metasomatic altered units on the contact between the Olympic Domain Wallaroo Group metasediments and the Hiltaba Suite Tickera Granite, Gawler Craton. Copper oxide mineralogy is dominated by malachite and chalcocite.
Photo Plates for 21AED001 may be viewed via the following link:
Photo Plates for 21AED002 may be viewed via the following link:
Drill targeting based on a new geological model has allowed Thor to vector in on key controlling mineralised structures and more importantly zones of higher copper and gold grades. Assay results from both 21AED001 and 21AED002 highlight grade uplift on the hanging wall side of the north-south trending controlling structure, validating the new geological model and structural controls on mineralisation.
Drillholes 21AED001, 21AED003 and 21AED005 (Section A-A’ 6,256,360mN), were drilled through the central portion of AE_5 (Figure 4), designed to validate the geological model and test areas, open at depth. The high-grade copper and gold intercepts in 21AED001, significantly above the MRE cut-off, opens the mineralisation up at depth, with 21AED005 pXRF copper readings highlighting the grade uplift along the controlling north-south structure.
A Cross section showing 21AED001, 21AED003 and 21AED005 may be viewed via the following link:
21AED004 (Section B-B’ 6,235,440mN) was drilled along strike to the north 21AED005, with pXRF reading validating geological model and higher copper grades along controlling structure (Figure 2, 3 and 5).
A Cross section showing 21AED004 may be viewed via the following link:
21AED002, AED006 and 21AED007 (Section C-C’ 6,235,600mN) were all drilled to the north of the AE-5 MRE domain, with assay results extending the known copper mineralisation along strike towards AE-8.
A Cross section showing follow up drillholes adjacent to 21AED002 and 21AED006 may be viewed via the following link:
Multi-element analysis of the assay results from both 21AED001 and 21AED002, highlights two distinct higher-grade zones of copper-gold mineralisation within a broader mineralised envelope. The lower of the two has a distinct IOCG geochemical signature – elevated Cu, Au, Mo, Co, Se, Bi & REE (Figure 7 & 8 log plots). This potentially reflects sulphide oxidation of primary mineralisation; whilst the upper zone reflects supergene weathered mineralisation. Once all assays are received a detailed geochemical analyses and modelling of the zones will be completed.
A Log Plot for 21AED001 showing IOCG signature may be viewed via the following link:
A Log Plot for 21AED002 showing IOCG signature may be viewed via the following link:
Remaining drill core is currently being prepared for sample submission to the laboratory, with all assay results anticipated in approximately 4 weeks.
In conjunction with the diamond drilling program a water bore was successfully developed for pump testing. This is part of the initial hydrogeological baseline work forming part of the ‘proof of concept’ for ISR, including water characteristics, porosity, and permeability testing. Subsequently preliminary metallurgical studies on potential lixiviants for copper and gold recovery will commence using ground water samples.
– Ends –
For further information on the Company, please visit www.thormining.com or contact the following:
Thor Mining PLC
Nicole Galloway Warland, Managing Director
Mick Billing, Executive Chairman
Ray Ridge, CFO / Company Secretary
Tel: +61 (8) 7324 1935
Tel: +61 (8) 7324 1935
Tel: +61 (8) 7324 1935
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