THE INSIDE STORY: Alliance Resources (ASX: AGS) is manager of the Wilcherry project Joint Venture, located in the mineral rich Gawler Craton of South Australia with Tyranna Resources (ASX: TYX).
Alliance (51%) and Tyranna (49%) struck the Wilcherry JV in 2016, when the latter wanted to concentrate on its Jumbuck project, but did not want to divest totally from the quality 1,200 square kilometres of tenements, which are considered prospective for gold and base metals.
The Wilcherry project Joint Venture comprises three priority areas, including the Zealous tin-base metals, Telephone Dam zinc-lead-sliver, and Weednanna gold prospects.
Alliance as operator of the Joint Venture recently commenced a program of reverse circulation (RC) drilling at the Zealous tin-base metals prospect, which it identified as a first-order conductive target via a helicopter-borne electromagnetic (HEM) survey during December 2016.
This was confirmed by a follow-up high-powered moving loop electromagnetic (MLEM) survey completed in March 2017.
“When we first came into the Joint Venture we recognised the project was under a significant amount, covering about 80 per cent of the tenement, of mostly shallow transported cover,” Alliance Resources managing director Steve Johnston told The Resources Roadhouse.
“From that we saw an opportunity to use airborne electromagnetics to search for buried massive sulphide deposits.
“There were two really good data bases of magnetics and gravity, but the next step was to fly a regional airborne EM survey.
“We did that and identified many late-time conductors, including the two big ones – the first at Zealous and the second at Telephone Dam.”
Alliance completed a moving-loop survey on both Zealous and Telephone Dam in March that confirmed the prospects to be conductor systems, being that there is more than one conductor at each prospect.
A program consisting five RC holes, totalling 1,500 metres, is being drilled to initially test the two conductors that comprise the Zealous target.
Three holes are planned to test the Zealous Main Conductor and two holes at the Zealous northwest conductor.
“The moving-loop survey conducted at Zealous confirmed a large southern conductor of 1500 metres by 1250 metres, dipping to the southwest at a depth around 100 to 200 metres and a northern conductor – more flat lying – 1500m by 750m and the interpreted depth to the top of that one was around 50 metres maximum,” Johnston said.
“There has been no previous drilling carried out into either of these conductors, however, there is some historic drilling 300m to the southeast of the southern conductor by Ironclad in 2012 as part of its search for iron ore deposits.”
The previous drilling at Zealous between 2012 and 2014 intersected sizeable tin grades, including:
20 metres at 1.29 per cent tin from 42m;
12.3m at 1.1 per cent tin from 119m; and
10m at 1.23 per cent tin from 128m.
“Because the initial analyses were for iron ore and base metals were not the focus, the lab reported missing mass in the iron suite XRF analyses,” Johnston explained.
“Introducing another analytical method showed up the presence of base metals, including an elevated level of tin.
“That resulted in Ironclad going back and looking at the project as a new tin target and they drilled around 25 holes that intersected shallow, but significant, tin intercepts.
“A couple of further holes in 2016 intersected lower grades whilst targeting a magnetic anomaly.
“However, our recent moving-loop survey showed the presence of the conductor system to the north and below the historic drilling.
“The Joint Venture has commenced drilling on the Zealous target and we are really looking forward to receiving the results of those holes.”
The MLEM survey data from Telephone Dam clearly confirmed the presence of weak bedrock conductors consistent with the HEM anomalism.
Two bedrock conductors have been defined with the northern conductor being strongest.
“Again, at Telephone Dam, there are two main bedrock conductors – a northern conductor that is around 1000 metres by 1000 metres in size interpreted to be around 150 metres to the top, and a slightly larger southern conductor 1500 metres by 1000 metres and a depth to the top of around 25 to 50 metres.”
Alliance has interpreted the conductors to potentially have some width/thickness to them and more complex geometry than simply a thin plate model approximation with constant dip.
Should this be the case, then Alliance expects the conductive unit could be intersected above the current modelled position.
“At Telephone Dam, there has been a lot of historic drilling carried out by a raft of owners since the 1980s for silver-lead-zinc,” Johnston said.
The historic drilling at Telephone Dam produced some impressive results, such as: 92m at 2.28 per cent combined lead and zinc with some silver credits, associated with the northeast corner of the Southern Conductor.
Upon completion of the drilling at Zealous, Alliance will commence a small program consisting three RC holes for 850m to test the MLEM conductors at the Telephone Dam zinc-lead-silver prospect.
The third target of the Alliance trinity is the Weendnanna gold prospect, which was another pre-existing project to evolve from the Ironclad legacy.
Ironclad viewed Weednanna as a magnetite prospect, and Trafford was keen on the gold potential of the prospect.
However, Ironclad was the operator and its view prevailed until 2015 when the two companies merged, resulting in Tyranna Resources.
“Whilst we were planning and flying the geophysics over the regional targets, we were keen to commence work at an advanced prospect and Weednanna fitted the bill,” Johnston explained.
“We couldn’t ignore that it had produced great gold results over a strike length of around 1.3 kilometres.
“We identified three target areas we considered to have potential to have high-grade, but which required further drilling.”
Alliance drilled those targets in March and produced outstanding gold intersections including:
49m at 6.3g/t gold from 45m, including 21m at 10.7g/t gold from 48m;
2m at 61.1g/t gold from 167m;
10m at 6.8g/t gold from 79m, including 3m at 15.5g/t gold from 81m; and
7m at 11g/t gold from 82m, including 4m at 17.6g/t gold from 84m.
Weednanna is the most advanced gold prospect in the Wilcherry project area, having originally been identified in 1997 as a strong gold-in-calcrete anomaly coincident with a prominent north-north-west-trending magnetic anomaly.
Successive drilling campaigns identified gold mineralisation associated with skarn alteration and brecciation in the contact aureole of the adjacent granite, however, these failed to fully unravel the structural and lithological controls on the distribution of gold.
Alliance is now systematically re-logging all available RC chips and diamond core from Weednanna with the objectives of identifying structural and lithological controls on the distribution of gold, constructing a 3D geological model of the prospect, and planning further exploration with a view towards defining a mineral resource.
A further program of RC drilling is planned to test for extensions to, and infill, high-grade gold intersections at Weednanna Targets 1, 2 and 3 returned from the recent RC drilling program.
This drilling will follow the drilling to test electromagnetic conductors at the Zealous and Telephone Dam prospects.
Alliance Resources Limited (ASX: AGS)
…The Short Story
51 – 55 City Road
Southbank, VIC, 3006
Ph: +61 3 9697 9090
Ian Gandel, Tony Lethlean, Steve Johnston