During licence Year 4, to 6th June 2000, Adelaide Resource Limited acquired EL 2188 “Minnipa” from Newcrest Mining 18/1/2000. The attraction of the tenement was in the discovery of high-quality gold-in-calcrete anomaly discovered in earlier...
During licence Year 4, to 6th June 2000, Adelaide Resource Limited acquired EL 2188 “Minnipa” from Newcrest Mining 18/1/2000. The attraction of the tenement was in the discovery of high-quality gold-in-calcrete anomaly discovered in earlier exploration of the area by Newcrest, which lies along the prospective Eyre Highway Trend first identified by Adelaide Resources on the adjacent Eyre Peninsula Joint Venture tenements. Exploration during the reporting period was entirely focused on the calcrete anomaly now referred to as the Barns Gold Prospect. A program of infill calcrete sampling (417), regolith mapping, the drilling of 50 RAB holes for 2558.5 m and 3 RC holes for 360 m. Six-meter composite samples were assayed for Au, Ag, As, Cu, Fe, Mn, Mo, Ni, Pb, Zn, Ca, and Mg, while any composite sample returning anomalous results were resamples at 1 m intervals and assayed only for Au. Petrological studies were completed on a number of drill chip samples. Analytical results show anomalous gold to be widespread. The pallid zone rarely contains anomalous gold due to geochemical depletion however the saprolite units, saprock and fresh lithologies all contain gold mineralisation. Calcrete samples were collected at 400, 200 and 100 m spacings proximal to the location of the original anomaly. Samples were analysed for Cu, Pb, Zn, Ni, As, Mo, Ca, Mg, Fe and Mn. The program effectively defined a cluster of geochemical anomalies termed the Barns Anomaly, with the main feature covering an area of 2.5 x 1.5 km with a coherent zone of 500 x 350 m >20 ppb Au. Regolith mapping was completed on 1:10000 scale to further the interpretation of the Barns anomaly. Observations were made both in field and from aerial photos. A Work Area Clearance Survey was completed on the 9th June 2000, a number of sites of significance to Aboriginal people including salt lakes and granite hills were identified within and adjacent to the licence area. Results of the work completed in the reporting period were considered encouraging with potential economic intersections of secondary and primary gold mineralisation. During licence Year 5, work was again entirely focused on the Barns Prospects, with the completion of 70 RC holes for 5082.8 m (RCBN-54 – RCBN-122), the completion of petrological investigations on drill chips and the completion of a ground magnetic survey with the assistance of PIRSA. The RC drilling aimed to gather primary zone geochemical and geological data. Variability of analytical results was noted with significant variation noted when results from samples that originally returned a high value, re-assayed retuned far lower results. Additional independent checks were made at a second laboratory, results were generally less variable but significant differences still appeared. It has been concluded that the variation in assay results may be the result of “coarse” gold at the prospect. The detailed ground magnetic survey covered 6 km2 at a 100 m line spacing, over the area of Barns already drill tested, with readings taken approximately every 1.5 m. The survey showed a subtle (~100nT) magnetic low in close coincidence with bedrock gold mineralisation. Adelaide Resources believe it is possible that the alteration process has destroyed accessory magnetite present within both the Hiltaba granodiorite and quartzite host rocks producing the negative anomaly. Several other magnetic lows, some with geochemical support, are also evident on the survey and form worthy exploration targets. Adelaide Resources believe that the results of the work completed at the Barns Gold Prospect in the fifth tenure year are encouraging. Potentially economic intersections of gold mineralisation were returned from a very large alteration system developed in a Hiltaba granitoid. The mineralisation remains open in many directions and based upon the widespread occurrence of anomalous gold and the size, intensity and style of the alteration system it is apparent that a substantial mineralised system has been discovered. During Year 6 of the project, and licence Year 1 of renewed licence EL 2845, exploration aimed to define the extent and nature of the mineralisation at the Barns Prospect and further investigation of the deeper levels of the Eastern Zone mineralised system. Calcrete sampling (216 samples) and reverse circulation percussion (RC) drilling (11 inclined holes for 1,522.7 m and 1,248 samples (RCBN-123- RCBN-133)) were completed. Calcrete samples were assayed for Au, Ag, As, Bi, Cd, Ca, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, P, Sb, V and Zn. Maximum calcrete gold assays were 25 ppb and 16 ppb from sample E28377 and E28379 respectively. Drillhole samples were assayed for gold only. Significant intersections include 32 metres at 1.05 g/t from hole RCBN-126 (including 4 metres at 3.47g/t) and 2 metres @ 67.6 g/t from hole RCBN-129. A trial IP survey was completed in August 2002 by Search Exploration. Response from sulphides associated with the gold mineralisation is poor. The latest calcrete sampling showed the gold anomaly at Barns to extend to the north for at least a further 800 metres. Drilling so far has been confined to a 1.4 km by 2km zone. The better drill results are from an area 300 m north-south by 200 m east-west. The improved widths and grades of gold mineralisation defined during this reporting period provide the possibility that Barns prospect may have a substantial tonnage of gold mineralisation with bulk mining potential. During Year 7 of the project and licence Year 2 of EL 2845, exploration included 2 calcrete sampling programs and 3 drilling programs. On the 27th May 2003 a joint venture agreement was announced between Adelaide Resource Ltd and the Newmont Australia Ltd Group to explore the Eyre Peninsula tenements held by Adelaide Exploration Limited. Newmont is committed to spend $1M per year for 5 years. Infill calcrete sampling (142) of the Northern Zone defined a new 2,200 metre target. While a regional sampling program (36) on a staggered 1.6 km grid was completed over portions of the tenement outside of the Gawler Ranges National Park that had not been previously sampled. The regional calcrete sampling did not locate any gold anomalism away from the Barns area. A program of 3 percussion/diamond cored holes (PDBN-134- PDBN-136) was completed for 583.1 metres and 435 samples in the Eastern Zone to investigate the geology and structural controls of the gold mineralisation. A 109-hole RAB/air core drilling program (5,706.2 m, 1,164 samples) was completed to obtain bedrock geochemical and geological information over previously untested or poorly tested parts of the extensive Barns calcrete geochemical anomaly. Targets tested included the recently defined Northern Zone, a south-eastern (White Tank) anomaly, and two features located in the south-western part of the area. Additionally, the density of bedrock RAB drilling was increased in the Western Zone to better define this attractive but poorly understood area of mineralisation. Seven reverse circulation drillholes (RCBN-240 -RCBN-246) for a total of 1,036 m and 906 samples were sited to test primary targets in the Northern, Western, Eastern and White Tank Zones. The third program of drilling, and the second RAB program, continued through the end of this reporting period. Fifty-two holes (RHBN-0247 - RHBN-0298) were drilled for a total of 3,113 m and 1,090 samples. At White Tank prospect, four closely spaced RAB holes were drilled in the vicinity of RHBN-234 (7 m at 10g/t gold) to determine the strike and dip of the mineralisation. Results showed that the mineralisation strikes northeast southwest and dips to the northwest at approximately 25 degrees. Four 50 m spaced traverses were RAB drilled to test the strike extent of the mineralisation. Promising secondary gold values hosted by weathered bedrock were intersected on three of the four lines. Relatively long intervals of anomalous gold occur in the north-western hole on each of the three mineralised traverses indicating the potential for an improvement in grade down-dip in the primary zone. The primary targets at White Tank then required testing using deeper reverse circulation drilling techniques. Pattern bedrock RAB drilling and one RC hole in this Northern Zone indicate that the calcrete anomaly is probably due to the presence of gold in a buried drainage system and is probably unrelated to the Barns primary gold system. Joint Venture partners, Newmont, undertook inhouse research to investigates surface sampling material, 18 calcrete samples were collected, and the gold assay results compared with that of soil fine fraction at the same location. Newmont concluded that the sampling of the soil fine fraction had no advantage over the current calcrete sampling method.