Wiluna delivers further exceptional hits incl 37.52m @ 10.77 g/t gold from namesake project

by Leena Thomas
Image: Wiluna Mining Corporation Limited

Wiluna Mining Corporation Limited (ASX: WMX) has reported high-grade results from a further 45 holes and 10,534m of resource development drilling at the Wiluna Mining Centre in Western Australia.

Significant results from drilling at Wiluna Mining Centre include 10.84m @ 29.39g/t and 23.92m @ 3.55g/t (within broader 37.52m @ 10.77g/t), incl 3.08m @ 100.53g/t, 1.64m @ 10.31g/t and 5.00m @ 6.82g/t; 5.76m @ 5.26g/t; 1.08m @ 25.24g/t and 5.70m @ 5.28g/t; and 12.00m @ 8.14g/t.

Wiluna Mining Centre

The Wiluna Mining Centre includes Wiluna Mine with its large sulphide resource at Bulletin, Happy Jack, Calvert, Essex, East Pit, and West Pit. The Wiluna Mining Centre also includes the Quartz Reef deposits of Golden Age, Galaxy, and Monarch.

Drilling at Wiluna

The company had commenced drilling at Wiluna Mining Centre to increase the level of confidence in the Mineral Resource at the Wiluna Mining Centre, increase the confidence in high priority mining areas in the 3 to 5 year mine planning window, and to confirm the Company’s Reserves (to be updated in January 2021).

WMX said that over 35,000m of drilling was completed in the first three months of FY2021 at the Bulletin, Calvert, Essex, and East Lode zones.

The company said that the programme at the Bulletin zone was designed to infill Inferred Resources within preliminary stope designs in the interim mine plan, with the aim to upgrade geological confidence to Indicated category.

WMX said that the programmes at Essex and Calvert zones were also designed to intersect Inferred Resource areas in the preliminary mine plan, with the aim to enhance geological confidence.

Exceptional drill results

WMX said that high-grade results were achieved from the drill programme at the Bulletin zone, Essex zone, and Calvert zone.

Bulletin zone

The company reported that the programme at the Bulletin zone achieved excellent results, with the lodes still open in multiple directions including the outstanding 37.52m @ 10.77g/t in BUUD0146.

Significant intersects included BUUD0127: 5.76m @ 5.26g/t; BUUD0142: 1.08m @ 25.24g/t and 5.70m @ 5.28g/t; BUUD0144: 1.11m @ 11.48g/t and 3.47m @ 9.30g/t; BUUD0146: 10.84m @ 29.39g/t and 23.92m @ 3.55g/t (within a broad halo intercept of 37.52m @ 10.77g/t); WURC0911: 12.00m @ 8.14g/t; WURC0916: 2.00m @ 14.45g/t and 2.00m @ 5.38g/t; WURC0917: 6.00m @ 4.75g/t; WURD0083: 1.60m @ 6.47g/t and 5.70m @ 2.70g/t; WURD0088: 3.00m @ 4.66g/t and 4.30m @ 6.42g/t (within a broad halo intercept of 38.00m @ 1.84/t); WURD0091: 3.14m @ 6.14g/t and 3.50m @ 2.79g/t; WURD0097: 1.34m @ 17.53g/t; and WURD0098: 7.41m @ 4.35g/t incl. 4.05m @ 6.08g/t.

The company said that the Bulletin results complement recently reported wide, high-grade intersections including 14.45m @ 17.16g/t, 7.40m @ 15.82g/t, and 19.56m @ 6.15g/t. WMX said that these results demonstrate that very high-tenor mineralisation remains in situ at Bulletin, at shallow depths close to existing mine development to allow for rapid and low-cost extraction.

Essex and Calvert zones

The company announced that excellent results were achieved from this programme at Essex and Calvert zones and possible extensions to the lodes remain open along strike and down-plunge.

Significant new intercepts from Essex and Calvert include WUDD0063: 7.89m @ 4.95g/t incl 3.89m @ 8.67g/t; WUDD0062: 5.00m @ 9.44g/t and 5.70m @ 5.28g/t; and WURC0910: 6.00m @ 6.95g/t and 3.00m @ 6.17g/t and 4.00m @ 3.50g/t.

WMX said that these results complement recently reported high-tenor intersections including 6.00m @ 53.73g/t, 8.00m @ 15.20g/t, 4.00m @ 24.46g/t, and 4.00m @ 17.47g/t.

Mine development plan

Wiluna announced that the five elements of the Company’s broader staged sulphide mine development plan include Stage 1 progress; drilling and resource development; reserves and mine planning; Stage 2 feasibility studies; and longer term development.

The company said that Stage 1 of the sulphide development plan will see the Company transition from its current production profile of producing 62kozpa from mining free milling ore through the current 2.1 Mtpa CIL processing facility, to initially producing on completion and fully ramped up approximately 120kozpa of gold and gold in concentrate. T

WMX said that this will be implemented using the current, recently refurbished crushing circuit, the previously expanded mill circuit and a new 750ktpa concentrator by October 2021.

Drill results validate Stage 1 target

The company announced that the drill results from each of the priority mining areas continue to validate the Company’s Stage 1 target of mining approximately 750,000 tonnes of underground sulphide ore per annum to produce, when fully ramped up, approximately 120,000oz per annum in gold doré and gold in concentrate commencing in October 2021.

WMX noted that supporting the sulphide development plan at the Wiluna Mining Centre is a Mineral Resource of 23.9Mt @ 4.89 g/t for 3.76Moz using a 2.5 g/t cut-off, within the Company’s global Mineral Resource of 143Mt @ 1.60g/t for 7.3Moz.

What’s next?

The company reported that follow-up resource definition drilling is likely, as mineralisation is interpreted to remain open in various directions.

WMX reported that to build upon the success of the programme to date, the drilling ahead would have the following aims.

  • Continue to increase sulphide Reserves for the Stage 1 development at shallow, high-grade, high-priority mining areas including Bulletin, Happy Jack, Calvert, Essex and East Lode.
  • Infill the Resource and add geological confidence to support the Stage 2 development with programmes from surface to a depth of 1,200m. The programme includes mine dewatering and development to access drilling positions for Stage 2 targets.
  • Discover new high-grade sulphide zones, with multiple targets identified “under the headframe”, to reveal the full potential of the large-scale gold system at Wiluna.

Management comments

Wiluna Mining Executive Chair, Milan Jerkovic said: “Exceptional drilling results continue to flow from high priority sulphide mining zones at the Wiluna Mining Centre. This is noteworthy because results will underpin our updated Ore Reserves estimate to be published in January 2021.

The Company is targeting high-grade zones, because every 1 g/t increase in the grade should result in an additional 25kozpa of production in Stage 1 and 50kozpa in Stage 2.

Indeed, the continued focus of our aggressive drilling campaign is to deliver rapid growth in high-grade Resources and Reserves through infill drilling of the existing large gold resource, and to discover new zones ‘under the headframe’. Very encouragingly, drilling continues to confirm that Wiluna is a very large, very high-grade gold system.”