An area located immediately north-west of Olary township has been explored for possible economic intrusive-related copper-gold-molybdenum mineralisation associated with high level Ordovician felsic igneous intrusions, as well as for...
An area located immediately north-west of Olary township has been explored for possible economic intrusive-related copper-gold-molybdenum mineralisation associated with high level Ordovician felsic igneous intrusions, as well as for Palaeoproterozoic to Mesoproterozoic basement-hosted iron oxide - associated copper-gold (IOCG) mineralisation, stratiform high grade metasedimentary / metavolcanic silver-lead-zinc mineralisation of the Broken Hill and Cannington styles, and chemical sedimentary haematite and magnetite iron ore hosted by the Neoproterozoic Braemar Iron Formation. The recent nearby discoveries of the White Dam gold deposit and the Blue Rose polymetallic skarn deposit have greatly increased the prospectivity of this area within the southern Curnamona Craton. Field work on the subject tenement commenced in licence Year 3 with a detailed gravity survey being acquired over the Faugh-a-Ballagh copper-gold mine prospect to identify drilling targets for potential IOCG style mineralisation. 81 stations were read on a 500 m x 500 m grid during November 2004. This survey successfully defined a gravity anomaly trending along strike to the west of the abandoned historic mine: a strong magnetic anomaly seen there corresponds to magnetite veining evident in the old workings. 31 rock chip samples were collected in the northern portion of the tenement during 2005, and some interesting uranium values were returned from the Domenic prospect near Ameroo Hill (e.g. 2.2% U3O8, plus 2.7% thorium, 0.25% cerium and 0.09% lanthanum), that are associated with a feldspar-dominant pegmatite. Across all of EL 2039, four discrete uranium targets were able to be defined, based on surface geochemical anomalies that correspond to radiometric anomalies noted on reprocessed airborne radiometric data. Pacific Magnesium Corp. rated these targets highly due to the important Crocker Well uranium deposit being located only 30 km away to the north-west. Late in 2006 further reconnaissance mapping and rock chip sampling defined a second zone of significant uranium geochemical anomalism lying 650 m south of the Domenic prospect pegmatite, across a soil covered plain. The four samples taken from the eastern end of a 100 m x 50 m outcrop consisting of quartz veined hematitic rock, albitite and gneiss returned results of 0.73% U3O8, 0.31% U3O8, 0.30% U3O8 and 0.29% U3O8 respectively, besides being anomalous in rare earth elements, and yielded radioactivity readings of up to 12,000 counts per second on a hand-held scintillometer. During the sixth licence year, the JV partners remodelled some airborne EM data relating to a steeply dipping EM anomaly located east of Ameroo Hill. North Ltd had previously tested this anomaly during 1996 by conducting very shallow RAB drilling (average hole penetration 2 m) that revealed concentrations of up to 2600 ppm Zn in a subcropping schist unit which is associated with a strong magnetic anomaly characteristic of Broken Hill Group strata. Lynas Corp. in 1998 drilled two RC holes into the interpreted EM anomaly source, but in PacMag's opinion both of these drillholes were collared too far north to allow an effective test of it, and only skimmed the top part of the target, returning intercepts of >300 ppm Zn from ~ 20 m wide zones near 166 m depth. PacMag planned to drill another two, deeper RC/diamond core holes each to about 300 m depth in a more southerly position, which would definitively test the EM anomaly and perhaps discover a multi-million tonne zinc deposit comparable to the Potosi or Rasp occurrences at Broken Hill. However, this particular programme of work did not eventuate. In June 2009 the partners commenced alternate drilling, completing 4 inclined RC holes for a total penetration of 260 m to test inferred extensions of the Domenic prospect uranium anomalies in a downdip position. However, the downhole sample assay results were generally disappointing, failing to deliver grades similar to the surface showings. A maximum value of 560 ppm U was obtained, and this, together with a lack of lanthanum at depth compared to the high cerium-lanthanum contents of the surface samples, suggested the presence of refractory primary uraniferous minerals. During July 2009, ten rock chip samples were collected at the Peryhumuck copper-gold mine IOCG prospect and submitted for a wide range of elemental analyses. The assay results showed significant copper and gold enrichment associated with some haematitic breccias (with iron grades commonly in excess of 20%) developed along an ENE-trending shear zone. Four of the ten grab samples returned copper grades in excess of 2% Cu, with a maximum of 7.57% Cu, and three of the ten samples returned gold grades in excess of 2g/t Au (maximum 5.19 g/t Au). The mineralised samples also showed strong anomalism in silver (grades in excess of 5 g/t Ag in three samples) and molybdenum (with three samples assaying in excess of 200 ppm Mo) as well as cobalt and bismuth. A single sample returned an isolated anomalous lead value (0.16% Pb). A consistently high level of sulphur in the samples suggests that the mineralisation was predominantly tied to sulphides prior to weathering. No further exploration activities were undertaken during the eight and ninth licence years, and tenure was allowed to lapse without renewal in July 2011. The obvious underperformance on Outalpa relative to the licence work commitments was commensurably offset by the joint venture's high expenditure elsewhere on its Olary Project acreage, with approximately $1 million spent on proving the extent and viability of the Blue Rose discovery.
More +