Recent announcements regarding the South Australian mineral and energy resources sectors
This update covers the May 2018 period and is compiled from information publicly released by companies.
Readers should refer to the latest information available on company websites, particularly in regard to making any forward investment decisions.
Previous news items:
- Alliance Resources
- Andromeda Metals
- Archer Exploration
- Auroch Minerals
- Gindalbie Metals – Torrens Mining
- Havilah Resources
- Hillgrove Resources
- Investigator Resources
- Leigh Creek Energy
- Renascor Resources
- Tyranna Resources – WPG Resources – Coombedown Resources
Alliance Resources reported on the regional gold potential at the Wilcherry Project, focusing on those areas within 5 km of Weednanna with the primary objective to assess the potential of Weednanna for economic development (ASX release 7 May 2018). Preliminary compilation of historic geochemical and drilling data includes:
- 5 m at 2.46 grams per tonne (g/t) Au from 159 m, including 3 m at 3.30 g/t Au from 161 m (08MAW008; Mawson prospect)
- 1 m at 4.09 g/t Au from 14 m (99UDSR029; Ultima Dam South prospect)
- intercepts >1 g/t Au (Mawson, Ultima Dam South and Weednanna North prospects)
- anomalous gold, >0.2 g/t (Ultima Dam and Ultima Dam North prospects).
Alliance is well advanced with this work and plans to establish a maiden mineral resource estimate in the first half of 2018.
Initial high purity alumina (HPA) metallurgical test work on a sample of Carey’s Well kaolin–halloysite feedstock returned a product with 99.99% alumina using an industry standard HCl two-stage dissolution precipitation process (ASX release 30 May 2018). Key impurities included silicon (66.84 parts per million, ppm), sodium (30.16 ppm) and iron (28.28 ppm), each of which Andromeda Metals expects to be further reduced by processing improvements moving forward.
The work was commissioned by Andromeda and Minotaur Exploration as part of their joint venture heads of agreement. Andromeda see the successful result as further strengthening the case for fast-tracking Carey’s Well deposit through the feasibility and mining approval processes.
A maiden exploration target has been announced for Archer Exploration’s Jamieson Tank manganese project of 15–25 million tonnes (Mt) at a grade of 8–12% Mn (ASX release 7 May 2018). It is based on historical results from 208 drillholes drilled by Archer and Monax Mining between 2008 and 2012, which intersected substantial widths of mineralisation over an extensive area.
The mineralisation predominantly comprises cryptomelane with the potential for both relatively high metal recovery and the production of electrolytic manganese dioxide. The mineralisation is open along the strike and at depth. Planned follow-up exploration activities include geophysical surveys, drilling (including diamond) and additional metallurgical test work.
Archer has entered into negotiations with the University of Sydney Commercial Development and Industry Partnerships for an exclusive licence to develop and commercialise intellectual property related to graphene-based quantum computing technology (ASX release 23 May 2018). The intellectual property has the potential to positively impact the quantum computing industry by developing and integrating critical componentry (qubits) that can operate under practical conditions.
Auroch Minerals is planning an aggressive, systematic exploration program for its Bonaventura base metals project on Kangaroo Island following recent encouraging results from reconnaissance rock-chip sampling of a number of prospective target areas (ASX release 11 May 2018). High-grade zinc (plus Pb, Cu and Ag) mineralisation has been confirmed at the Grainger target (previously referred to as the Bonaventura target). Best results include:
- 28.00% Zn, 1.44% Pb, 0.22% Cu and 19.5 g/t Ag
- 21.30% Zn, 3.06% Pb, 0.45% Cu and 42.8 g/t Ag
- 6.72% Zn, 2.17% Pb, 0.89% Cu and 30.6 g/t Ag
- 3.1% Zn, 2.40% Pb, 0.91% Cu and 51.6 g/t Ag.
Reconnaissance sampling of waste dump material from historical artisanal mine workings at the Kohinoor gold target in the southeast of the tenement has also confirmed high-grade gold mineralisation. Best results include:
- 33.30 g/t Au
- 17.40 g/t Au
- 8.98 g/t Au.
Reprocessing and interpretation of existing geophysical data has identified 17 target areas (ASX release 21 May 2018). An induced polarisation survey will be undertaken in June over three of the higher priority targets (Dewrang, Grainger and Vinco) with drilling expected to follow in the third quarter of 2018.
At the company’s Arden base metal project near Port Augusta, reinterpretation of historical geophysical data has confirmed potential sedimentary exhalative base metal mineralisation and a new 8,500 line kilometre high-resolution aeromagnetic and radiometric survey is expected to be flown shortly (ASX release 17 May 2018). A drill program at the highest priority targets is on schedule to commence early in the third quarter of 2018. Permitting processes for drilling are well advanced.
Gindalbie Metals – Torrens Mining
A preliminary mine scoping study update on the indicated Cu–Co–Ag resources at Gindalbie Metals’ Mount Gunson project has been completed and board approval given to commence Stage 2 of the farm-in with Torrens Mining, i.e. a prefeasibility study (ASX release 23 May 2018). Scoping study highlights include:
- Updated total indicated mineral resources for the Windabout and MG14 deposits:
- 1.83 Mt at 1.24% Cu, 334 ppm Co and 14 g/t Ag (MG14)
- 17.67 Mt at 0.77% Cu, 492 ppm Co and 8 g/t Ag (cutoff grade 0.5% Cu equivalent; Windabout).
- Preliminary test work supporting further evaluation of a conventional floatation-based circuit as a base case producing split copper- and cobalt-rich concentrates from MG14 and Windabout.
- Results of the Emmie Bluff Cu–Co–Ag prospect initial concept study presenting a strong case to undertake further work on Emmie Bluff.
Under the farm-in agreement, on proceeding to Stage 2 – prefeasibility study, Gindalbie is committed to spending $2.5 million in return for a 51% interest in the project.
Havilah Resources released an updated supergene Cu–Au resource at North Portia (ASX release 15 May 2018) which includes:
- new inferred resource estimate for upper oxide gold zone of 490,000 tonnes (t) at 1.17 g/t Au for 18,400 ounces (oz) of gold (applying a lower cutoff of 0.5 g/t)
- new measured resource estimate for supergene sulfide Cu–Co–Au zone of 3,856,000 t at 0.73% Cu, 154 ppm Co and 0.51 g/t Au (applying a 0.4% Cu equivalent lower cutoff)
- maiden cobalt resource of 594 t in cobaltian pyrite host.
The updated total resource (oxide and sulfide) contains 101,400 t of copper metal, 594 t of cobalt metal, 258,800 oz of gold and 5,630 t of molybdenum metal.
Havilah considers North Portia a natural extension of Portia – being on the same mining lease and having access to existing Portia infrastructure, processing plant and mining partner (Consolidated Mining and Civil Pty Ltd, CMC) – therefore not having a significant impact on the company’s ability to advance its higher priority Kalkaroo and Mutooroo projects.
Havilah’s recent purchase of Exploration Licence 5393 from Exco Operations (SA) and Polymetals (White Dam) secures 100% ownership of the approximately17 km2 Grants iron ore basin, which includes the Grants iron ore deposit (ASX release 18 May 2018). The purchase also potentially increases Havilah’s coverage of the Mutooroo cobalt district, bridging the gap between Havilah’s Wilkin’s Cu–Co–Au project (ASX release 30 July 2012) and the Mutooroo Project Cu–Co–Au resource.
Historical Mutooroo drill core has been resampled and analysed as part of the company’s Mutooroo prefeasibility study (ASX release 30 May 2018). Best results include:
- 17.1 m at 1.66% Cu, 0.16% Co and 0.18 g/t Au from 162.0 m (DDMM21A)
- 9.4 m at 1.72% Cu, 0.19% Co and 0.63 g/t Au from 469.4 m (DDMM7)
- 6.9 m at 1.32% Cu, 0.13% Co and 0.07 g/t Au from 637.7 m (DDMM15D1).
Havilah expects to complete the prefeasibility study before the end of 2018.
Repairs and refurbishment to Hillgrove Resources’ primary crusher were successfully completed and the processing facility is now running at full capacity (ASX release 24 May 2018). The opportunity was also used to bring forward other planned preventive maintenance, including a SAG Mill girth gear rotation.
An update on metallurgical results carried out for Investigator Resources’ Paris silver project prefeasibility study has been released (ASX release 7 May 2018). Preliminary results indicate that cyanide leach trials achieved weighted average silver recoveries around 74% with a range of 65% to 89% for the three main geometallurgical domains.
Further investigation is required to augment silver recovery. Investigator aims to conclude the processing options in June 2018. Metallurgical performance is critical to its decision to bring the Paris project into production, therefore a key component of the prefeasibility study.
Leigh Creek Energy
Two of three activity notifications required to commence the pre-commercial demonstration stage of the Leigh Creek Energy project have been approved by the government regulator (ASX releases 15 May 2018 and 29 May 2018). Leigh Creek Energy also reported that site construction was underway and drilling of the in situ gasification process wells about to commence with planned gas operations expected in the third quarter of 2018.
Marmota’s April drilling program at the Aurora Tank gold project saw 50 RC drillholes completed with depths ranging from 50 to 195 m for a total 3,988 m (ASX release 23 April 2018). Assay results are expected in mid June. Aurora Tank is located 50 km northeast of Challenger gold mine, which has produced in excess of 1.2 Moz of gold.
Geochemical results from cobalt targets at Renascor Resources’ wholly owned Olary project have significantly enhanced cobalt prospects in the Bulloo Creek and Shorts Dam areas and the company is intending to drill test these as soon as possible (ASX release 24 May 2018).
At Bulloo Creek, soil sampling has confirmed coincident cobalt at surface over an area of approximately 800 x 400 m. Rock-chip sampling at Shorts Dam has reaffirmed previous strong cobalt drill intervals that included 15 m at 0.14% Co and 0.07% Cu from 19 m (including 1 m at 0.64% Co from 32 m) in Esso Minerals Australia drillhole SP04. Detailed sampling of gossanous subcrop and float has returned multiple cobalt assays in excess of 100 ppm with the most encouraging results in the area of previous Esso drilling (SP01, SP02)..
Tyranna Resources – WPG Resources – Coombedown Resources
A new mineral resource estimate for the Jumbuck gold project has been released by Tyranna Resources (ASX release 30 May 2018). The new total of 319,000 oz of Au is an increase of 100,000 oz, representing a 46% increase on the previous January 2017 estimate (ASX release 24 January 2017). The update is based on shallow drilling with mineralisation around 100 m from surface. Tyranna considers the Jumbuck deposits potentially amenable to open cut mining, but with all deposits interpreted to be open at depth there is still excellent potential for resource increases with future drilling. It will now commence the planning, in association with joint venture partners, of first-pass scoping studies to evaluate the potential to advance Jumbuck toward feasibility studies.