An upland area located approximately 100 km south-west of Whyalla on the eastern Eyre Peninsula, and with its eastern boundary running parallel to the coast at a distance of 15 km from Cowell and Franklin Harbour, is being explored for uranium,...
An upland area located approximately 100 km south-west of Whyalla on the eastern Eyre Peninsula, and with its eastern boundary running parallel to the coast at a distance of 15 km from Cowell and Franklin Harbour, is being explored for uranium, graphite, manganese and iron ore. No field work was done during the first licence year. After UraniumSA bought the tenement, early exploration primarily addressed the potential for finding buried structurally controlled, high grade primary vein-type epigenetic uranium mineralisation in the Palaeoproterozoic basement rocks, and also possible younger, also buried unconformity style uranium mineralisation, similar in character to those deposits found in Canada's Athabasca Basin and the Alligator Rivers region of the Northern Territory in Australia. During January 2007, a reconnaissance ground IP survey using a 200 m x 100 m dipole-dipole array was acquired along three traverses located in the south-western part of the licence area, to profile the Blue Range Beds for chargeability anomalies. A number of these were detected and modelled for depth and intensity. During February 2007, part of an airborne magnetic/radiometric/digital terrain model survey was flown over the licence along NE-SW flight lines spaced 200 m apart, to generate 1352 line km of coverage. The aim of this survey was to assist in mapping probable buried faults and shear zones which could have related primary uranium mineralisation potential. Reconnaissance aircore drilling was performed in May 2007, of 113 vertical holes for a total penetration of 2063 m, both to test the causes of selected IP anomalies and to sample the underlying bedrock for lithology and geochemistry, as well as to map the thickness of the transported sedimentary cover. The aircore drilling found that the target Blue Range Beds had effectively been eroded away in the places tested, although some thin remnants of them were intersected in several holes, and there are small remnants outcropping at other localities. A shallow-sourced IP anomaly having associated bedrock copper and zinc anomalism was identified (the Boothby prospect). During licence Year 3, UraniumSA conducted further follow-up of the Boothby anomalies with soil calcrete geochemical sampling (384 samples assayed) to try to define the extent and orientation of the anomalism. A weak correlation was observed between the aircore drillhole bedrock sample geochemistry and the calcrete assay results, i.e. the trace element distribution displays a NW-SE trend, parallel to the strike of the Blue Range Beds, which also coincides to the present ground surface's general topographic drainage direction. In September 2008, during licence Year 4, UraniumSA acquired a small part of an airborne EM (RepTEM) survey over the Boothby prospect, flying 59.9 line km along eight east-west lines spaced at variable distances apart, using a 35 m mean sensor height above the ground surface. Again, the aim was to better define the extent and orientation of the anomalism prior to doing more drilling. No field work was done during the fifth licence year, while processing and interpetation of the whole 485 line km set of RepTEM survey data was effected. During 2011, under the alternate JV management of Pirie Resources, exploration on now renewed EL 4693 became focussed towards determining the manganese, iron ore and graphite potential of bedrock in the deeper, hinge zone section of the Campoona Syncline, which is buried mainly below >100 m thickness of cover. Previous company exploration results obtained from there were reviewed, and stored drillhole samples that contain graphite were sent for petrographic description. Another airborne EM (RepTEM) survey was flown during July 2011, of 156.5 line km along SE-NW orientated flight lines spaced either 100 m or 50 m apart, using a 30 m mean sensor height above the ground surface. Conductivity highs evident in the survey data were thought to correlate well with known graphite occurrences, while CDI sectional projections made of the data showed the syncline's structure well. On the basis of the subsurface geophysical mapping, 9 RAB holes for 451 m were drilled into two potential graphite-rich targets, Campoona South and Grid 2, during October 2011. Some other RAB drilling was done by Pirie Resources elsewhere on EL 4693 during February 2012, to test targets at Campoona West, Salt Creek, Emu Plain and ?Mangalo South-west [but no clear mention of these holes was provided to PIRSA by the company]. Late in 2011, two selected graphite schist samples, one a rock chip taken from weathered outcrop and the other of drill cuttings, were sent to overseas mineral processing experts for them to conduct laboratory testwork on separating the graphite grains and then determining the grain size distribution of the mineral concentrates. They reported that both the separated graphite fractions are predominantly very fine grained (less than 71 microns) and that the graphite in them is still mostly intergrown with mica. During licence Year 7, the majority of work performed by Pirie Resources consisted of a large appraisal and delineation drilling programme undertaken across the several graphite occurrences identified within the Campoona Syncline, in order to define a JORC Code-compliant estimated mineral resource. Drilling of 5 diamond holes and 37 RC holes at the Campoona Shaft and Campoona Central graphite occurrences provided data that were used as of September 2012 to estimate combined Measured, Indicated and Inferred resources, at a 5% Total Graphitic Carbon (TGC) lower cut-off grade, of 2.527 Mt containing 310,800 t of graphite. The individual resource category figures were also calculated [see main report]. Additional exploratory drilling, and a more detailed, prospect scale airborne EM survey, were also performed to define inferred strike extensions to the Campoona resource, as well as to try to identify other graphite occurrences amenable to extraction. A total of 113 inclined or vertical step-out RC holes were completed during the reporting period. Some material was identified further to the south as a part of the main occurrence trend, and some limited mineralisation was encountered to the north; both of these areas are affected by structural complexity, and follow-up drilling is necessary to understand the geology. Further metallurgical testwork on Campoona graphite mineral concentrates involving tailored grinding steps and advanced flotation methods was reported to have yielded upgraded graphite concentrates in excess of 98% TGC purity, a level of quality which Pirie Resources said is rare for an ultrafine natural graphite product. The capacity to produce such a quality product is expected to open up a wide range of market opportunities to the company for selling high grade concentrates (+95% & +99% TGC) at a generally higher market pricing. Also, Pirie Resources thinks that the economic so conferred by mining the Campoona material may allow the mining and processing of lower cut-off grades, larger reserves, and greater selectivity in mining. Consequently, many more resources may be available. In expectation of taking out a mining lease over the presently delineated resource areas, Pirie Resources commissioned consultants Golder Associates Pty Ltd to conduct baseline flora and fauna studies at Campoona during the period September to November 2012. In other important work, Pirie Resources' ground-based activities undertaken on the western side of EL 4693 have led to the discovery of a region of epithermally altered Hutchison Group basement rocks which the company has named the 'Donna Complex'. Interpretation of regional geophysical data supports a model of a deeply buried elongate intrusive igneous body underlying the region, which has overlying veined and brecciated hydrothermally altered zones formed on its north-western and south-eastern flanks. Sampling of the various altered country rocks has identified different styles of alteration related to the lithologies examined: - alunite alteration within what possibly were quartzites - silicification of dolomites - massive growth of tourmaline in pegmatites. Pictorial examples of these features are included in the 2012-2013 annual report. On the basis of this find, Pirie Resources' immediate intent was to begin exploring the region for epithermal gold via detailed geological mapping, surface geochemical sampling and other work necessary for defining deep drilling targets. Rock chip sampling was begun, and 180 samples were submitted for multielement analysis, with some significant minor gold results returned from the north-western breccias, and a general spread of elevated base metal anomalism. During licence Year 8, Pirie Resources' main activity was to perform an infill drilling campaign at the Campoona Syncline graphite occurrence to define a maiden inferred JORC-compliant resource at the Campoona Central deposit. For this, 28 angled RC holes for 1447 m plus one 60 m deep steeply inclined HQ diamond hole were completed. Using a 5% Total Graphitic Carbon (TGC) lower cut-off grade, a resource of 520,000 t of graphite was estimated. At the Campoona Shaft deposit, geotechnical drilling of 3 angled HQ diamond holes for 297 m plus 4 vertical 9 inch auger holes for 120 m was undertaken respectively to investigate ground conditions to inform mine planning studies, and to obtain a larger volume of rock material to use for future metallurgical testwork. For epithermal gold exploration, bedrock geochemical drilling of 2 angled RC holes for 139 m was performed at Bartels prospect to try to find additional vectors towards mineralisation. Further rock chip geochemical sampling was done at the Donna complex (239 samples laboratory assayed). During licence Year 9, no field work was done. Pilot plant scale metallurgical testwork was commenced to refine the design of individual ore processing operations, ahead of advancing the Campoona Project mining feasibility study. Systematic testing of a composite sample collected from the starter pit zone at the Campoona Shaft deposit was taken through ore preparation and bulk rougher and scavenger flotation. Archer provided samples of final Campoona graphite concentrates to a number of international companies for them to conduct detailed testing, as a possible precursor to entering into either offtake agreements or taking a direct equity stake in the project. One company distributed the sample to a number of affiliates to conduct detail assessment including the manufacture of graphene materials and testing of these graphene products into high-tech electronic componentry. Archer began sole funding $200,000 of University of Adelaide research over two years into the production of graphene from its future South Australian graphite output, in product forms which will have broad industrial, environmental and agricultural applications. As of 30/9/2014, background studies contributing to the draft mining lease proposal for the Campoona mine were said to be ~75% completed. 2 groundwater supply and monitoring wells were drilled to depths of 121 m and 91 m respectively to pump test for flow rates and water quality, with a view to the deeper hole acting as a possible source of water for future graphite processing based at Sugarloaf. A sustained yield of 5 l/s was indicated, which is more than the envisaged process water requirements. Attempts were made to reprocess the 2012 ground EM survey data to try to discriminate signatures that represent areas of economic flake graphite from areas that are either not economic or contain amorphous graphite. During licence Year 10, studies were made into the performance of Campoona natural graphite versus synthetic graphite in lithium-ion batteries. Creating even, fine micronisation of the graphite appeared to confer an advantage to the natural material in anode charge capacity. Graphene was successfully prepared from concentrated Campoona graphite (>99% graphitic carbon) by a novel, direct liquid phase mechanical exfoliation method developed by the University of Adelaide. This mechanical exfoliation process is scalable, and requires fewer steps compared with conventional methods, which involve the preparation of graphene oxide and then a chemical reduction to produce graphene. On 14/5/2015, the draft Mining Lease Proposal (MLP) for the Campoona Project was lodged with DSD for review. This MLP covers the mining of the Campoona Shaft graphite deposit and the conduct of related ore processing at Pirie Resources' Sugarloaf property located near Darke Peak. A small soil sampling program (69 samples) was undertaken at Bartels in follow up to previous drilling in the area. A low lever Au anomaly (10 ppb) was detected. Twelve rock chip samples were collected south of the Bartels Au anomaly. Samples were collected in follow up to a previous sample of quartz-muscovite pegmatite/greisen with a reported a tin level of 0.12%. The new samples returned tin values above 100 ppm. During the eleventh licence year, the reporting period has been dominated by continued Mine Planning and Scoping studies for the Campoona Graphite Project. Ongoing processing studies and equipment selection (via test work) has continued to enhance the projects viability. A small number of rock samples were taken for the identification of lithium bearing minerals, there are none of economic significance. The Campoona Mining Lease Application was lodged with DSD on 10th November 2016. Rock chip samples (8) were taken to follow on a historical report of spodumene within the tenement. The location of the outcrop was identified and revisited but was found to be dominantly diopside, and no pegmatites were observed. Samples were then taken from the roadside and known pegmatite locations, however none indicated anomalous lithium. During licence Year 12, the reporting period was dominated by the continued Mine Planning and Scoping studies for the Campoona Graphite Project (MLA), including processing studies and equipment selection. The Mining Lease for the Campoona Graphite project (ML 6470) was granted 5th December 2017. During licence Year 13, no fieldwork was completed as an assessment for the manganese potential was undertaken. Further to this "Emu Plain" was revisited as a copper-molybdenum prospect. In 2017 (19/10/2017) an area of 200 square km of EL 5804 were partially surrendered from the largest Area B block along the eastern portion of the block. No work had been done. In 2018 (15/11/2018) an area of 43 square km from the north east corner of the Area B block were partially surrendered. No work had been done. On 13/1/2021, 228 square km of the largest, Area B block of EL 5804 were partially relinquished, that comprised ground in the south and north-east of this block. No work had been done there.