During the 2014 project reporting year, licensee Adelaide Resources undertook a research and development phase surface-based biogeochemical and field portable X ray fluorescence (FPXRF) spectrometric sampling programme over its Baggy Green gold...
During the 2014 project reporting year, licensee Adelaide Resources undertook a research and development phase surface-based biogeochemical and field portable X ray fluorescence (FPXRF) spectrometric sampling programme over its Baggy Green gold prospect on EL 5120, to follow on from such work undertaken at the Barns prospect in October 2013 by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) as part of a wider, multi-site innovative research study. The Baggy Green gold prospect is located about 5 km south-east of Barns and was discovered by the company in 2004 when drilling of a large gold-in-calcrete soil geochemical anomaly revealed subsurface mineralisation. Significant drill intersections which were then made at Baggy Green included 8 m @ 4.79 g/t Au, 11 m @ 2.30 g/t Au, and 24 m @ 2.33 g/t Au. Because Baggy Green lies within a sand dune covered area, now the Pinkawillinnie Conservation Park, that in the past was deemed unsuitable for agricultural or pastoral use and thus retains its native vegetation cover, it was selected as suitable for sampling the CSIRO recommended mallee gum species leaf matter to try to detect biogeochemical anomalies that may indicate the presence of buried mineralisation. 196 samples of these type of eucalyptus leaves and stems were collected on a 400 m x 50 m grid over a 2.6 square km plot that includes two areas of drill-confirmed subsurface gold mineralisation, and were laboratory assayed for a suite of 33 trace elements including gold. The assay results confirmed that leaves sampled from trees growing above both the southern and northern zones of known mineralisation contain anomalous levels of gold. The results also revealed that the biogeochemical gold anomaly associated with the northern zone of bedrock mineralisation extends further to the west than the known extent of subsurface mineralisation, so suggesting that further investigation in this area may be warranted. Anomalous silver concentrations in the leaves were seen to closely mimic those of gold, thereby indicating corroborative support for the gold results, and in the northern zone they too also extended further west than the known extent of subsurface mineralisation. Other trace elements including antimony, cadmium, sulphur and zinc also produced vegetation biogeochemical anomalies which are semi-coincident with the known bedrock mineralised zones. An in situ FPXRF spectrometric analysis was made of a soil sample taken from below each mallee tree sampled in the biogeochemical survey, but the geochemical scan results obtained by this method showed that no soil trace element definitively outlined the northern gold zone at Baggy Green. Only cadmium was elevated over the mineralised area, however this correlation was less obvious over the southern zone. In November 2014, new joint venture farm-in partner Investigator Resources flew a 3500 line km detailed helicopter-borne magnetic/radiometric/DTM survey over EL 5419 along east-west flight lines 100 m apart, using a 30 m mean sensor elevation above the ground surface. Subsequent interpretation of the processed aeromagnetic data identified a number of preliminary epithermal silver-gold targets at the interpreted intersections of inferred mineralising dykes and structures. Later, field geological mapping located outcrop of prospective siliceous epithermal breccia and ironstone breccia rubble that supported the perceived potential. During the 2015 project reporting year, Adelaide Resources performed a diamond drilling campaign on the Barns prospect within EL 5092 and on the Baggy Green prospect within EL 5120, undertook FPXRF soil sampling plus biogeochemical sampling on the Empire prospect, and modelled the maiden gold resource at the White Tank prospect on EL 5120. In April through June 2015, 7 eastwards inclined diamond cored holes for 1287 m were drilled, four at Barns and three at Baggy Green, to test beneath surface gold anomalies. All holes encountered good and wide gold intercepts at both prospects, thus demonstrating for each the continuity of the individual mineralised zones that are contained within the broader mineralised envelope. At Empire prospect, the geochemical sampling done on a 200 m x 50 m grid produced copper anomalies that do not coincide with those derived by calcrete sampling. Also, although copper, nickel and vanadium values obtained by FPXRF scans of soil reflected those obtained by co-located biogeochemical sampling of mallee tree leaves, the values of silver, arsenic and molybdenum differed between the media, implying that the trees may have a varying, less consistent uptake mechanism for the more volatile elements. Consequently, now Adelaide Resources thought that the existing drilling which had targeted calcrete copper anomalies would not have fully test the potential of the regolith copper anomalies generated by biogeochemical sampling or FPXRF scans of soil. Late in the year, several rounds of resource modelling and geological interpretation addressed the Barns, Baggy Green and White Tank gold deposits, incorporating the results of the recent diamond drilling. The work entailed generating detailed digital terrain models (DTMs), 3D geological surfaces relating to weathering and rock types, and 3D mineralisation wireframes generated from triangulating sectional interpretive strings. On 15/10/2015, the company announced to the ASX a combined exploration target figure of 2.5 to 3.5 Mt @ 1.3 to 2.0 g/t Au for the three deposits. Barns was regarded as the most likely of the three to soon be proven economic to mine, as it has the biggest resource and largest drillhole inventory. In the first half of the year, decisions were made to fully surrender three of the project licences and partially surrender a fourth. EL 4690 Yaninee was all dropped on 11/3/2015, EL 4781 Buckleboo ditto on 12/5/2015, EL 5257 Pildappa ditto on 6/5/2015, and one part of EL 5120 Corrobinnie on 8/5/2015 (for details, see the separately held progress/final report in Env 12719). Work undertaken by Investigator during 2015, the first full year of that company's farm-in to EL 5419 Thurlga Ramp, included: - the acquisition of high-resolution aerial photography across the entire tenement; - reprocessing of historic REPTEM and TEMPEST airborne EM survey data from the tenement area; - continued interpretation of data from the November 2014 detailed aeromagnetic/radiometric/DEM survey flown across the entire tenement; - the acquisition in January-February 2015 of 127 ground gravity survey readings along two traverses to confirm the presence of a large regional, +5 mGal gravity high within the tenement, and to provide more data for geophysically modelling it; - soil geochemical sampling covering ~60% of the tenement on a 500 m x 500 m grid (2128 x minus 180 microns sieved soil samples collected for laboratory assaying); - field geological mapping and general prospecting; - rock chip geochemical sampling of outcropping skarn and altered carbonate lithologies (45 grab samples collected for laboratory assaying); - recovery of drill chip trays from storage and relogging of selected drillholes. Compilation and interpretation of the above-described surface geochemical data led to the identification by Investigator of the highly silver anomalous 'Wide' [as in a bowled cricket ball] soil anomaly (Ag >300 ppb), which also has a strong copper-gold signature. During the 2016 project reporting year, in April, a follow-up biogeochemical sampling survey and concurrent soil geochemical FPXRF scanning were conducted by Adelaide Resources at the Empire and Baggy Green (North) prospects, closing in the sample density to 50 m x 50 m to infill around earlier detected copper and gold anomalies, besides extending the initial coverage at Empire for a further ~1 km to the north, south and west with FPXRF scans taken on a matching 200 m x 50 m grid. Mallee tree leaves were again used for the biogeochemical samples. The results of this new work defined closely coincident copper and uranium anomalies at Empire that may be related to clayey areas favoured by the mallee species Eucalyptus oleosa. The anomalism at Baggy Green was starting to reveal both the likely orientation and strike extent of underlying bedrock gold mineralisation, when correlated to the geometry and tenor of existing drillhole intercepts based on gold-in-calcrete targets. None of the anomalies at Empire had yet been drilled. In the light of this promising upside, Adelaide Resources submitted proposals to DSD for grants of PACE Initiative subsidy funds to help it drill the many new coherent biogeochemical and soil FPXRF anomalies at Empire and Baggy Green (North). In July 2016, after several rounds of resource modelling and geological interpretation had been undertaken, a maiden JORC (2012) - compliant resource for the Barns gold prospect was announced to the ASX. This estimate totalled 2.11 Mt @ 1.6 g/t Au, using a 0.5 g/t Au cut-off grade, for 107,000 ounces of contained gold. This resource had been classified into 380,000 tonnes of Indicated category and 1,730,000 tonnes of Inferred category, based on data from 327 drillholes. Independent consultant Mining Plus Pty Ltd assisted with the resource estimation. The gold occurs in flat lying supergene zones overlying moderately dipping, quartz vein - associated primary gold lodes within Archaean Tunkillia Suite granodiorite. The main lodes as mapped are open to the south and down dip, and excellent potential to increase the Barns resource exists. Five nearby gold prospects also show strong potential to deliver additional resources. In October-November 2016, an RC drilling campaign was performed at the Baggy Green (South) and (North) prospects, the latter located only 5.5 km south-east of the Barns deposit, aiming to build on the above described maiden resource figure. It was designed to test a gently dipping zone of mineralisation where historical intercepts had included 11 m @ 3.55 g/t Au and 24 m @ 2.04 g/t Au, including 7 m @ 5.56 g/t Au. 23 eastwards-inclined RC holes for 2515 m were drilled along six traverses, and ten of them encountered significant gold mineralisation, including the best grade intercepts, to 9.32 g/t Au, so far recorded at Baggy Green (South). At Baggy Green (North), the new holes gave evidence of a large hydrothermal system that has generated a mineralised zone with a somewhat different orientation to that seen at Baggy Green (South). On 1/7/2016, Adelaide Resources partially surrendered ground on EL 4968 Waddikee Rocks and EL 5120 Corrobinnie (see Env 12897 for the relevant progress report). In the separately operated work programme for EL 5419, farminee Investigator during early 2016 made further interpretation of the geochemical targets that it had identified at the Wide, Starburst, Swinger and Yorker prospects. It was decided to apply for a grant of PACE Initiative subsidy funds to assist in drilling these, besides for test drilling selected other geochemical and geophysical anomalies which could also have silver prospectivity, or which could reveal base and precious metals formed within the Hutchison Group rocks in trap settings associated with the Uno Fault. A work proposal was submitted to DSD on 28/4/2016. This successfully attracted PACE funding after 15/8/2016 as approved collaborative Year 9 drilling project DPY9-11 (for the separately held final report of the drilling results, see Env 13187). During the period February-March 2017, 20 open vertical aircore holes were completed for a total penetration of 1076 m. Significant and unexpected downhole intersections of graphite were encountered within magnetic Hutchison Group metasediments of the Thurlga Syncline at the Ironstone North and Ironstone prospects. The four holes drilled into the Ironstone North target were successful in defining the near-surface position of the Uno Fault. Although the objectives of these holes were met, there was no indication of potential Imiter-style alteration or silver + base metal mineralisation in either the foot wall or hanging wall rocks abutting the fault, and so the decision was made to not proceed with the proposed diamond hole. The aircore drilling done at the Wide silver-in-soil buried epithermal porphyry target returned narrow intervals high in lead-zinc, uranium, cerium and niobium. Low levels of silver, copper, nickel, bismuth and tin were also detected over significant widths. In other work, a further 37 rock chip and 1464 infill soil geochemical samples were collected and assayed. The infill sampling done to 250 m x 250 m precision revealed to Investigator some poor repeatability of the initial 500 m spaced soil sampling results. The Thurlga Fault zone was modelled using all available geophysical data. A minor amount of work was begun to investigate the lithium potential of pegmatites located on EL 5419. During the 2017 reporting period, EL 5064 was allowed to expire, EL 5120 was replaced by EL 5953, and EL 6001 replaced EL 4968 after a 248 km2 reduction through relinquishment. Activities during the reporting period included metallurgical testwork undertaken by the operator on samples of gold mineralisation from both the Barns and Baggy Green deposits. Mineral Resource estimates for Baggy Green (1.56 Mt at 1.64g/t gold for 82,400 ounces at a 0.5g/t cut-off grade) and White Tank (0.17Mt at 1.92g/t gold for 10,900 ounces at a 0.5g/t cut-off grade) prospects were generated, and in addition to the pre-existing Mineral Resource estimated for the Barns deposit in 2016, a total Resource of approximately 200,000 ounces of gold has been defined at the Wudinna Gold Camp. A Heads of Agreement was signed between Andromeda Metals and Lady Alice Mines Pty Ltd in late 2017, for a Farm-in and Joint Venture comprising all Exploration Licences within the Eyre Peninsula Project AEA, excluding EL 5419 “Thurlga” which will be removed from the AEA upon its renewal. On ground exploration was limited to EL 5419, where Investigator completed a partially PACE funded aircore drilling program [See ENV13040 (CNO:2039924) for detailed results]. The program saw 20 aircore holes drilled for 1076 m. The aim of the drilling was to test soil anomalism from previously completed soil surveys across the tenement, and to investigate the Uno fault as a potential host for silver mineralisation. During the 2018 reporting period EL 5350 “Acraman” was replaced as EL 6262, EL 5381 “Pinkawillinie” was replaced as EL 6317 and reduced by 30km², and EL 6131 “Corrobinnie” was reduced by 69km2. Lady Alice Mines Pty Ltd lead a series of detailed technical studies including structural diamond core analysis, project-scale geochemical analysis, and geostatistical analysis. These studies progressed the understanding of the continuity of mineralisation at the Barns and Baggy Green deposits, while establishing important geochemical relationships as pathfinders for hydrothermal mineralisation across the project area. No physical samples or drilling was conducted on the project during the reporting period.