Lachlan Fold Belt
As part of the Ardea Prospectus preparation, a significant gold prospect has been generated for the Lewis Ponds project around the Godolphin Fault, a shallow east-dipping domain boundary structure separating the Ordovician Macquarie Arc in the west from the Silurian Hill End Trough in the east. From southeast to northwest, the structure hosts gold mining centres and targets from McPhillamys, Springfield, Mt Shorter, Calula and Copper Hill East. This Godolphin Fault trend is held within Ardea’s tenement package, a 50km strike of continuous tenure abutting the McPhillamy’s deposit in the south and the Commonwealth (Silica Hill) deposit in the north.
Yeoval Porphyry Copper-Gold-Molybdenum-Rhenium Project (ELA5368, recommended for grant) (Ardea 100%)
Yeoval (ELA 5368) is located within the Macquarie Arc, 60km northeast of the Northparkes copper-gold mine. The tenement application covers an area of 138km² and is intensely mineralised with more than 60 historic copper workings trending in a north-easterly direction, along a 20km strike. The project area encompasses the eastern section of the Early Devonian Yeoval Complex, with the major host being the Devonian-aged Naringla Granodiorite including gabbro-diorite and quartz monzo-diorites. The co-magmatic Canowindra Volcanics of the Cudal Group occur to the east and south. The Ardea exploration target is a large tonnage porphyry copper-gold-molybdenum-rhenium system.
This report section contains exploration results and estimates reported by ASX-listed Augur Resources Limited on 17 September 2012 under the JORC Code 2004.¹ The information has not been updated to comply with the JORC Code 2012, and it is uncertain whether following evaluation or further exploration work that the estimate will be able to be reported in accordance with the JORC Code 2012.
¹ Augur Resources has not consented to the use of the historical geological report reference in this announcement. This section contains exploration results and estimates reported by Augur Resources Limited on 17 September 2012 under the JORC Code 2004. The information has not been updated to comply with the JORC Code 2012, and it is uncertain whether following evaluation and or further exploration work that the estimate will be able to be reported in accordance with the JORC Code 2012.
The known Yeoval deposit comprises two main near-surface zones of bornite-chalcopyrite mineralisation. Initial drilling in 1972 produced best intercepts of 42.7m at 0.93% Cu and 18m at 0.8g/t Au. Drilling in 2008 by Augur Resources produced best intercepts of 90m at 0.90% Cu and 0.14g/t Au and 50m at 0.54% Cu and 0.48g/t Au. Augur Resources² reported on 17 September and 2 December 2008 an Inferred Mineral Resource in compliance with JORC 2004 guidelines and based on this, Augur Resources considered an Exploration Target of approximately 10Mt – 13Mt at grades of approximately 0.38% Cu and 0.14g/t Au as achievable.³
³ The potential quantity and grade is conceptual in nature and there is insufficient information to estimate a Mineral Resource and it remains uncertain if further exploration will result in the estimation of a Mineral Resource in this area of drilling.
|Hole ID||Grid E (m)||Grid N (m)||EOH (m)||Declin / azimuth (°)||From (m)||To (m)||Width (m)||Cu (%)||Au (g/t)|
|YZ-04||654 137||6 377 651||385.9||-55/102.5||182.7||266.2||19.1||0.6||0.66|
|This table represents data from an Augur Resources announcement on 17 September 2012 to the ASX. The background details of the data have yet to be ascertained and application has been made by Ardea to the NSW Department regarding release of the relevant comprehensive data-set to open file. The above information is included to validate that the Yeoval deposit is significantly copper-gold endowed and so warrants further investigation. Copies of Augur’s several Yeoval announcements are available by contacting Ardea.|
Mt Aubrey Epithermal Gold-Silver Project (ELA5369, recommended for grant) (Ardea 100%)
Mt Aubrey (ELA 5369) is located at the east contact of the Macquarie Arc Ordovician andesites some 30km northeast of Parkes and 30km southeast of Peak Hill.
The property was acquired by Ardea as an epithermal gold system hosted in Upper Silurian to Lower Devonian-aged Dulladerry Volcanics, a bimodal subaerial suite of quartz eye porphyry with rhyolitic ash-flow lapilli tuff, pyroclastic and breccia and amygdaloidal basalt. Gold mineralisation is typically hosted by 0.5-3m thick chalcedonic epithermal quartz veins and stockworks. All assays reported in Table 5 below are from open file reports and are not able to be verified by Ardea.
Although an epithermal-style of gold mineralisation, the Mt Aubrey mineralisation isn’t refractory, with the published run-of-mine grade (3.73g/t Au) returning 95.7% recovery in historic metallurgical test work.
Gold mineralisation at the Mt Aubrey vein system remains open at depth and along strike, as the historical drilling done by BHP Gold was only designed to define shallow oxide resources. The Mount Aubrey deposit was mined by BHP Gold in 1990 and 1991 as shallow open-pit satellite operations to the Parkes Gold Mine. It is estimated that up to 120,000 tonnes of ore at 3.3g/t Au was trucked to Parkes for processing. As part of the operating agreement with the landowner all three of the small open-pits were back filled.
It is presumed that the shallower of the drill intercepts as reported above were mined in the BHP open-pits. Historic pit pick-ups will be sought to quantify the status ore positions beneath the historic pit floors.
In 2007, Aurelia Metals Limited⁴ completed three diamond core holes beneath the former Mt Aubrey Gold Mine for a total of 916.6m. The holes were designed to test the down dip extension of high grade epithermal quartz veining mined in the Mt Aubrey open-pits. Holes MAD002 and MAD003 each intersected broad zones of epithermal quartz-carbonate vein stockworks associated with epidote, sericite and bleaching alteration and minor sulphides.
⁴ Aurelia Metals Limited has not consented to the use of the historical geological report reference in this announcement.
|Hole ID||Grid E (m)||Grid N (m)||EOH (m)||Declin / azimuth (°)||From (m)||To (m)||Width (m)||Au (g/t)|
|It is yet to be determined through historic pit surveys which of these intercepts have been extracted in previous mining operations. Anecdotal reporting suggests very shallow open-pits, being some 20-30m deep as determined by stripping ratios. Their inclusion in this Report is solely to demonstrate that the Mt Aubrey system is gold-endowed and warrants further evaluation.|
At the Mt Aubrey South prospect drill hole MAD004 intersected a broad zone hosting abundant mineralised crustiform textured quartz-carbonate-pyrite veining with a gold intersection of 88m at 0.22g/t Au from 2m. The gold mineralisation in MAD004 represents an un-mined new gold-bearing structure to the south of the main Mt Aubrey vein system.
The Blue Hills prospect is an area of outcropping, gold bearing veins and minor workings 2km along strike to the northwest of Mount Aubrey. Rock chip samples of up to 13.4g/t Au have been recorded and two costeans returned results of 2m at 1.35g/t Au and 6.5m at 1.40g/t Au. The area between Mt Aubrey and Blue Hills is mainly covered by modern alluvium but is also thought to contain quartz veining.
The Emu Swamp prospect is located 3km to the east of Mt Aubrey and contains outcropping veining with rock chip gold values to 3.3 g/t Au associated with pyritic alteration. The 6km Blue Hills – Mt Aubrey – Emu Swamp trend represents a significant epithermal vein system target.
Mt Aubrey along with the adjoining Yeoval tenure is interpreted by Ardea as the manifestation of a major NE-trending zoned porphyry copper-gold-molybdenum-rhenium to epithermal gold-silver intrusive centre.
Wiseman’s Creek Gold-Copper Project (ELA5378, recommended for grant) (Ardea 100%)
The Black Bullock prospect is located at Wiseman’s Creek, 35km southeast of Bathurst, NSW. Epithermal gold mineralisation within the tenure is hosted largely within Late-Silurian – Early Devonian-aged slates, shales and sediments of the Kildrummie and Campbell’s Groups, with geology through the centre of the tenure comprising the andesitic Ordovician-aged Rockley Volcanics.
Mineralisation has been reported as predominantly associated with silicified zones with epithermal textures such as open-space filling in quartz veins, quartz vein breccias, chalcedonic silicification and colloform banding. The units strike NNW and dip steeply eastwards.
The Wiseman’s Creek area was held as EL2098 by Windsor Resources⁵ during the 1980s and was part of a JV arrangement, which saw a total of 80 RC and three diamond holes drilled between the years 1985 - 1989. In Windsor’s 1988 Annual Operations report, the major historic gold mine production was noted as being from Black Bullock Mine, reporting production of some 40,000oz of silver and 2,098oz of gold from 4,700 tonnes of ore (at an average grade of 14g/t gold). Three main areas of interest were identified, some within State Forest and some on freehold land.
⁵ Windsor Resources has not consented to the use of the historical geological report reference in this announcement.
At the gold prices of the day, the deposit was not considered economic, however gold intercepts at shallow depths were reported that warrant further investigation. Table 6 above lists only some of the more significant gold intercepts recorded in the Windsor Annual Report. An additional 23 RC and 3 diamond drill holes (not listed in Table 6) contained significant intercepts at or above 0.5g/t Au. In 2006 Central West Gold⁶ completed an IP survey and drilled follow up RC holes based on modelling of the earlier historic drilling and which reportedly contained a best result of 3m at 0.36g/t Au from 9m.
⁶ Central West Gold has not consented to the use of the historical geological report reference in this announcement.
|Hole ID||Grid E (m)||Grid N (m)||EOH (m)||Declin / azimuth (°)||From (m)||To (m)||Width (m)||Au (g/t)|
|The above table represents historic data from GS1988_277 Windsor Resources report, recorded as a statutory requirement, for the NSW government department. The quality of the data has yet to be ascertained as historic QAQC work was poorly reported, but is included to establish that the Wiseman’s Creek prospect is gold-endowed and warrants further investigation.|
Duckmaloi Tungsten prospect
From 2012 to 2014 part of the tenement area now held by Ardea was held by Resmetco Ltd⁷ who explored for tungsten within a prospect known as “Duckmaloi” hosted within skarn style mineralisation. The prospect itself was estimated in an open file report to have an Exploration Target⁸ of approximately 375,000 tonnes at 0.2% WO₃ The potential quantity and grade is conceptual in nature and there is insufficient information to estimate a Mineral Resource and it remains uncertain if further exploration will result in the estimation of a Mineral Resource in this area of drilling.
⁷ Resmetco Ltd has not consented to the use of the historical geological report reference in this announcement.
⁸ An Exploration Target is a term used within the JORC2012 Code for an estimate of the exploration potential of a mineral deposit. As used in this release the stated Exploration Target is based upon the parameters described in the text, however the potential quantity and grade is conceptual in nature and there is insufficient information to estimate a Mineral Resource and it remains uncertain if further exploration will result in the estimation of a Mineral Resource in this area of drilling.
The existence of this deposit style as well as the nearby epithermal occurrences does suggest evidence for a larger mineralizing system and also warrants further investigation.