The Whundo project (100% owned) is a high-grade brownfield copper-zinc project with significant resource expansion potential. Whundo is a VMS style Resource, which is typically characterised by multiple deposits within a cluster. This is evident through the historical discovery of the Whundo, Ayshia and Yannery deposits while recent drilling and subsequent downhole EM by has confirmed additional promising prospects including at Austin and Shelby.
The Whundo project comprises of two mining licences (M47/7 and M47/9) and a miscellaneous license (L47/163) located approximately 40 km southsouthwest of Karratha in the West Pilbara region of Western Australia, covering an area of approximately 9 km2 within the West Pilbara Mineral Field. Access is via the sealed road to Tom Price heading south from Karratha then onto a mine road into the historical mine site.
The known copper and zinc deposits at Whundo are confined to a single stratigraphic horizon as a series of NW to NNW plunging shoots that outcropped as a sinuous line of discontinuous goethite-hematite gossans that can be traced for some 500 metres along strike. Individual ore shoots have a restricted strike length and are commonly 1-5 metres thick but reach a maximum thickness of 20 metres in the hinge zone of two small upright synclines in the axis of the major synclinal structure where they form the Whundo deposits.
The stratigraphic sequence at Whundo has undergone upper greenschist to lower amphibolite grade metamorphism, and is overprinted, in part, by hornblende hornfels contact metamorphism. These units have been folded about a moderately north plunging (25°-45°) synformal structure.
The West Whundo deposit outcropped as a gossan folded around a synclinal nose. The gossan was about 135 metres in length and up to 10 metres wide in the core of the syncline which plunges shallowly to the north. The gossan was surrounded by chloritic and sericitic schists, and with volcanic rocks present in the sequence.
Secondary copper mineralisation at West Whundo is present in two zones within the syncline; a southern zone centred about 75 metres to the north of the gossan, and a northern zone centred a further 90 metres to the NNE. The southern zone has a diameter of about 60 metres and the northern about 30 metres.
Figure 1: Whundo project location
Exploration by Fox Resources Ltd (Fox) in 2006 identified a mineralised zone within the Yannery prospect but peripheral to the historically mined area. This previous work by Fox included RC drilling for a total of nine holes and a fixed loop electro-magnetic (FLEM) survey. The Fox drill sample assay results included:
Artemis Resources (ASX:ARV) also undertook reconnaissance drilling to the NW of Yannery in 2018 aimed at testing for a down plunge extension to the mineralisation reported by Fox. One hole proved successful with the following results reported:
Figure 2: Local geology of the Whundo project area
In early 2022, GreenTech undertook a maiden 4,974m RC drill program at Whundo and Ayshia to test multiple drill-ready targets aimed at growing the existing JORC 2012 compliant resources at Whundo, as well as lateral and deeper extensions to the eastern and western lobes of the Whundo resource.
At Whundo, the Company drilled 25 holes for 3,838m, with significant intersections returning:
Figure 3: VMS deposits, prospects and targets at the Whundo project area
Greentech followed up the 2022 drill program with successful drilling in early 2023. This allowed the Company to identify new mineralised events at the Austin and Yannery prospects and to increase its mineral resource estimate (MRE). The assay results from this drilling included the following intercepts;
Austin
Hole 23GTRC001
Elevated zinc, gold and cobalt were also intercepted, including:
Yannery
Hole 23GTRC009
The combined Whundo and Ayshia resources are shown in Table 1 below (refer ASX announcement dated 12 April 2023 for full details).
Table 1: Combined Whundo and Ayshia JORC 2012 Mineral Resource Estimate
| Ore Type | Grade Range | category | Tonnes (kt) | Cu (%) | Zn (%) | Cu Metal (t) | Zn Metal (t) | Total
Metal (t) |
| Whundo | >0.25 | Indicated | 4,271 | 1.05 | 0.90 | 44,755 | 38,334 | 83,089 |
| >0.25 | Inferred | 0.854 | 1.39 | 0.45 | 11,876 | 3,811 | 15,685 | |
| Ayshia | >0.5 | Inferred | 0.916 | 1.3 | 2.3 | 11,908 | 21,068 | 32,976 |
| Total | >0.5 | Ind & Inf | 6,041 | 1.14 | 1.05 | 68,539 | 63,213 | 131,752 |
*Whundo deposit resource reported in 2018 using LME metal prices Cu US$6,058/t, Zn US$2,457/t and using 0.5% CuEq cut-off grade
**Ayshia deposit resource reported using LME metal prices for 6/5/2022; Cu US$9,428/t, Zn US$3,828/t, Au US$1,833/oz, Ag US$22.38/oz and using a 0.5% CuEq cut-off grade
Figure 4: Whundo / Austin projected section