The Kurnalpi-Randals Project is located south east of the old Kurnalpi mine workings about 95 km north east of Kalgoorlie, in the Coolgardie Mineral Field in Western Australia.
The project area comprises of:
- Steeple Hill Iron Project
- Kurnalpi East (Colour Dam, Anti Dam)
- Kurnalpi North (Halfway Hill)
- Kurnalpi South
- Jones Find
- Duchess of York
The Kurnalpi area has a history of gold mining, which available records indicate has produced in excess of 580 kg gold (18,650 ounces) from 14,292 tonnes at an average grade of 40.4 g/t gold. During the reporting period for the annual report, exploration work was carried out on Halfway Hill and Colour Dam prospects.
Regional Geology
The prospects are located in the south eastern part of the Eastern Goldfields Province of the Yilgarn Craton, where the geological and structural settings are complex.
The Eastern Goldfields comprises a series of attenuated northerly trending greenstone belts, which have been intruded by and are enclosed within similarly elongate granitoids plutons and complexes. Anastomising regional scale faults, mostly of sinistral strike-slip shears, dissect the province. However, broad-scale stratigraphic correlations still persist across these structures.
The regional stratigraphy comprises a lower basaltic unit, overlain by komatiite, followed by an upper basalt unit (with komatiite affinities) which in turn is overlain by a sequence of felsic volcanic and volcaniclastic rocks. Clastic sedimentary rocks unconformably overlie this sequence.
The komatiite is interpreted as a regional marker that extends across the Eastern Goldfields. However, other units vary laterally whilst felsic volcanic rocks occur at numerous intervals throughout the sequence. Researchers have subdivided the Eastern Goldfields into tectonostratigraphic domains bounded by major faults.
Recent mapping by the Geological Survey of Western Australia (GSWA) suggest division of the region into domains based on distinct stratigraphic, lithologic and structural features, bounded by regional faults and substantial shear zones such as the prominent Avoca shear.
This feature is readily apparent in the aeromagnetic data. A broad synclinal hinge zone has been identified to the immediate east of the Colour Dam Prospect. The Colour Dam syncline is a complex fold structure comprising a sequence of mafic volcanics overlain by felsic volcanics and fine grained meta-argillites and banded iron formations. The felsic volcanics comprise part of a major eruptive centre, which in the vicinity of Colour Dam was the subject of exploration for volcanogenic massive sulphide (VMS) deposits in the late 1970s.
Steeple Hill Iron Ore Project
Discovery of Iron Mineralisation at Lindsay Dam tenement.
Background
The Lindsay Dam tenement area and environs have previously been explored for nickel and base metals in the early 1970s, after which time the majority of exploration in the area focused on gold.
In May 2008, Fairstar's Exploration Manager began researching the presence of banded iron formations (BIFs) in the area. Further data search and enquiry on the potential presence of an "iron resource" in the tenement area was then carried out.
Historically, most exploration activity in the area has focused on base metals and gold. However, earlier explorers had carried out a reasonable amount of airborne geophysical work in the area, which on examination confirmed the presence of magnetic BIFs in the centre of tenement E28/1672, and extending to the surrounding area.
To physically confirm the presence of iron mineralisation in the area field reconnaissance was conducted on 18th and 19th June 08, and outcrops of iron mineralisation in the form of hematite, goethitic-hematite, canga, iron scree and BIF were recorded. In addition 23 rock chip samples were collected and analysed for iron and related elemental composition.
The iron discovery was made at tenement E28/1672, 110 km east of Kalgoorlie, and is the first of its kind in the area previously known for its gold and base metals prospectivity. The tenement is also in close proximity to major rail infrastructure, with the Trans Australian Railway passing 23 km south of the tenement area. The host BIF structure at the Lindsay Dam iron discovery is in excess of 15km in length and has a north-south orientation. It is highly folded and faulted, and four bands of BIFs varying from 10m up to 100m in width have been identified to date.
The potential BIFs extend beyond the E28/1672 boundary. As a result, the Company has applied to the Western Australian Minister for Mines and Petroleum for exploration rights for iron at the Lindsay Dam tenement, and in the Company's tenements to the north and south of the tenement E28/1672.
The Company has a 100% interest in E28/1766 and in regards to E28/1672 holds the precious metal rights and retains a first to last rights of refusal to purchase for all other minerals.
Regional Geology
The tenement lies within the Norseman-Wiluna greenstone belt of the Archaean Yilgarn Craton. The regional stratigraphy comprises mafic volcanics overlain by felsic volcanics which underlie fine-grained slates with local banded iron-formation. Minor ultramafic flows and gabbro sills are locally prominent along the mafic-felsic volcanic contact.
The regional syncline (Steeple Hill Syncline) occupies the centre of the tenement (E28/1672). In detail it is a complex structure and is inferred from a fold hinge outlined by banded iron formations (BIFs).
Local Geology
The tenement geology is structurally complex, consisting of north to northwest trending Archaean greenstone terranes with moderately magnetic Banded Iron Formation (BIF) horizons, mafic and ultramafic meta-volcanics and intrusives and weakly to moderately magnetic felsic volcanics. In the eastern part of the tenement north-south trending ridges of chert crop out with associated laterite and a large granitoid (interpreted) intruding the rocks of the eastern portion of the tenement.
The sedimentary rocks in the tenement outcrop poorly apart from cherts and banded iron formations, which stand out as ridges with pronounced scree slopes. The remaining poorly exposed sediments are silty, fine grained pelites possibly with some tuffaceous component. An east-north-easterly striking mafic to ultramafic dyke, informally known as Celebration dyke, passes from west to east in the southern part of the tenement. Additionally, a north east striking negative magnetic lineament with no apparent expression on-ground runs from the Randall Siding to Mount Charnleigh, passing through the tenement.
Recent Exploration
Recent work carried included; reconnaissance field visits and collection and analysis of 216 grab/rock chip samples for iron (Fe) and related elements.
Download Steeple Hill exploration results (PDF, 316 KB)
Outlook
In view of the types of iron material (goethitic-hematite, canga, iron scree and BIF bands) present at the tenement as well as rock chip sampling results, magnetic signature of the host rock, structural setting [presence of synclinal structure (Steeple Syncline) in the centre of the tenement, folding and faulting, etc.] and strike length of BIF bands, the discovery area looks to be highly potential for a commercially viable iron resource.
On receiving Government approval the Company will plan an extensive exploration programme, which will include further rock chip sampling, additional confirmatory work through the acquisition and analysis of available geological and regolith mapping, airborne magnetic and radiometric survey and a first pass of 10,500m drilling (10,000m RC and 500m diamond), sampling and analysis program. The Company's aim will be to confirm a JORC resource estimation in due course.
Kurnalpi North (Halfway Hill Prospect)
The Halfway Hill Prospect is located 3 km north west of the old Kurnalpi town site and forms part of exploration licence E28/465. Geological mapping of the exploration licence and environs by the Geological Survey of Western Australia along with aeromagnetic and air photographic interpretation by the Company's geologists suggests the presence of favourable host rocks and structures bearing gold mineralisation.
The geology of the Halfway Hill Prospect is dominated by a north-north westerly trending suite of mafic and ultramafic rocks bounded by mafic-intermediate volcanic and dolerite-gabbro intrusives.
The western contact of the mafic-ultramafic sequence is bounded by the Avoca Shear, a major structure considered responsible for localising gold mineralisation in the area.
Much of the tenement area is covered with colluvium and laterite deposits; effectively masking the structural and lithological information over the Prospect land. To date, exploration work at the tenement suggests that the area has good potential for yielding a sizable gold resource.
During 2008, the work included field reconnaissance, search and procurement of previously unavailable information, detailed study of all information, drilling of 1,807 metres RC percussion along 12 holes, sampling, and assaying of samples from the drill program (taken at 1 metre intervals).
Halfway Hill Exploration
An airborne magnetic-radiometric survey is planned for the project area to assist in selecting new drill targets for a 5300 metre drill program (5000 RC percussion and 300m diamond) along 30 holes to test deep extensions of gold mineralisation at the Area 9, Halfway Hill and Jones Find prospects.
The drill program will follow on, and provide further confirmatory data, to a highly successful 2008 drilling campaign at the Kurnalpi-Randalls Project.
Kurnalpi East (Colour Dam-Anti Dam Prospects)
The Colour Dam-Anti Dam Prospects are located 8 km south east of the old Kurnalpi townsite and cover lands of five tenements (E28/699, P28/789, P28/958, P28/993, and P28/994).
At Colour Dam gold and base metal mineralisation occurs in two distinct styles:
- Shear controlled, sheeted vein array quartz-sulphide-gold mineralisation associated with strong quartz-sericite - pyrite alteration.
- Complex brittle fracture controlled crack seal vein arrays of quartz-sulphide-gold associated with widespread quartz-sericite-pyrite alteration of the propylitically altered host dolerite.
During 1970s Colour Dam and its environs was explored for its base metal potential by companies such as, Amax Exploration (Australia) Inc, Aquitaine Australia Minerals Pty Ltd, and ESSO Exploration and Production Australia Inc. Aquitaine drilled eight diamond drill holes (at wide distances apart) and made eight intersections (in 3 holes) of 1m each with zinc values ranging from 1.1% to 1.9%.
The geology at the Prospect largely comprises a basic to felsic sequence of volcanic and volcano-sedimentary rocks ranging from ultramafic komatiites through tholeiitic basalts and dolerites through andesites to dacitic and rhyodacitic volcanic and volcaniclastic end members overlain by late tuffaceous argillites and banded iron formations.
At Colour Dam, the basic volcanic and volcaniclastic rocks are intensely altered to quartz-sericite-carbonate and pyrite is in association with quartz-sulphide vein arrays developed within shear zones associated with gold mineralisation.
In addition to the exploration potential of the Kurnalpi-Randalls Gold Project, the Company has a stockpile of about 5,000 tonnes of material at the Colour Dam Prospect, excavated by an earlier tenement holder, which contains around 2.5 g/t of gold.
Fairstar's drilling in the area has intersected anomalous values of copper, lead and zinc and copper flakes have also been observed in the stockpiles surrounding the Colour Dam pit. The feasibility of heap leaching the stockpile material for gold, and the possible extraction of other metals, will be examined over the coming months. Detailed mapping and channel sampling of the Colour Dam pit faces to understand the pit geology, structure, and mineralisation is also planned.
Kurnalpi South
Background
The prospect area is extensively covered by colluvium and laterite and is largely underlain by a northerly striking sequence of ultramafic, mafic to intermediate volcanics and intruded by dolerite to gabbroic dykes and sills.
The Avoca Shear, which is believed to have acted as a major conduit for gold containing mineralising solutions in the area, traverses to the west of the Area 9 Prospect.
Additionally, late stage, northeast trending secondary shears traverse the prospect and environs in the Kurnalpi Area, and these are considered to have directed the hydrothermal gold bearing fluids suitable for forming of shear hosted-quartz vein array style gold deposits. This view is supported by abandoned gold mine workings, which are mainly aligned (north east) along these faults/shear zones and at intersections between these structures (Figure 6).
In addition to these geological observations, Area 9's potential is further strengthened by the high-grade gold intersections obtained by previous explorers in the area:
- Two 3m intersections @ 7 and 14.2 g/t gold in drillhole KRC 13, 7m @ 11.5 g/t gold in drillhole KRC 24, 11m @ 10.9 g/t gold in drillhole KRC 32, and 2m @ 19.6 g/t gold in drillhole KRC 55.
- Additionally, the gold mineralisation at the Prospect is open at depth along dip and to the northwest.
Area 9 Prospect
The 2008 work programme included field reconnaissance, search and procurement of previously unavailable information, detailed study of all information, drilling of 2,379 metres RC percussion along 25 holes, sampling, and assaying of samples from the drilling (taken at 1 metre intervals).
After the positive results of 2007-2008 drilling, a further program of 2,000m of RC percussion and 100m of diamond (tail to RC percussion) drilling to test for deeper extensions of mineralising systems is underway.
Duchess of York
Duchess of York Gold and Base-Metals Project
The Duchess of York Project covers land across prospects P25/1856 to P25/1858 and is located at about 70 km south east of Kalgoorlie in the Bulong District of the East Coolgardie Mineral Field of WA.
More than 80 per cent of the project area is covered with colluvium. Recent study of available information suggests that the Project has the potential to host a reasonable size gold resource - both near surface (0-50 metres) and at depth, exceeding 100 metres. To unearth sub-surface geology and structures of the Project area an airborne magnetic-radiometric survey over the Project areas is scheduled to be flown in conjunction with Kurnalpi-Randalls magnetic-radiometric survey.
Jones Find
Background
The Jones Find Prospect (P25/1836) is located at about 50 km east of Kalgoorlie and 200m north of the Trans Australia Railway Line and covers about 70 hectares.
Several phases of exploration drilling (RAB and RC drilling, varying from 30m to 200m) have been undertaken at Jones Find since the 1980s. The RAB drilling outlined an extensive blanket of supergene gold mineralisation - 2.4 metres in thickness, about 400 metres east-west in width and 1.2km north-south along strike - and the RC drilling confirmed the presence of gold mineralisation in fresh rocks at depths greater than 195m (e.g.; JFC 23 with 1m @ 2.56g/t gold from 195m; JFC 28 with 1m @ 1.49g/t gold from 196m).
The study of available data indicated the possibility for a range of mineralised situations within the fresh rock in the tenement. The 2007-2008 drilling program was designed to intersect deeper mineralisation, likely to occur within the "fresh rock."
Regional Geology
The prospect is located within an Archaean quartz monzonite, known as Juglah Granite. The granite contains highly altered greenstone remnants.
Geology
The prospect is characterised by a total lack of topographical relief and is covered by recent alluvium and colluvium.
Evidence of underlying rock types and structure is confined to old mine shaft dumps and pits, together with several trenches and drill cuttings produced during exploration in the tenement over previous years Lateritic profile in the area is well developed and intersected in drill holes from surface, between 20 and 30 metres.
Based on mine dumps and available exposed mine faces, the tenement is considered to contain a mainly northerly striking, steeply dipping sequence of quartz-sericite-clay and quartz-sericite-biotite rocks which, as observed in the vicinity of old workings, are frequently sheared and schistose. Also, there appears to be a number of intrusive felsic quartz feldspar and feldspar porphyry bodies associated with the general lines of workings.
Structurally, the tenement is located on the eastern flank of the south plunging Bulong anticline. The western margin of the underlying granitoid basement coincides with a major northwest striking shear (Majestic shear/fault). The Jones Find Prospect is inferred to lie on a subsidiary splay of this major shear zone.
Recent Exploration
The work programme included field reconnaissance, search and procurement of previously unavailable information, detailed study of all information, a 3,418 metres RC percussion drill program along 35 holes, and sampling and assaying of samples from the drilling (taken at 1 metre intervals).