Recent announcements from the South Australian mineral and energy resources sectors
This update covers the November 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
- Archer Exploration
- Auroch Minerals
- Boss Resources
- Havilah Resources
- Leigh Creek Energy
- Magnetite Mines
- OZ Minerals
- Petratherm Ltd
- Renascor Resources
- Western Areas
Latest results from the September 2018 drilling program at the Weednanna gold prospect have been released by Alliance Resources (ASX release 29 November 2018). Twenty-eight reverse circulation holes were drilled to extend gold mineralisation at Shoots 1, 4, 5 and to test for gold mineralisation associated with a major quartz vein in the immediate hangingwall at Shoot 1, where historic drillhole 00WDRC072 returned 48 m at 2.0 grams per tonne (g/t) Au from 54 m, including 7 m at 5.4 g/t Au from 69 m and 2 m at 16.0 g/t Au from 98 m. Of the 28 holes, 24 (86%) reported intercepts >1 g/t Au. Best results include:
- 20 m at 12.44 g/t Au from 104 m, including 8 m at 28.57 g/t Au from 112 m (18WDRC027)
- 3 m at 5.97 g/t Au from 64 m in (18WDRC029)
- 5 m at 3.06 g/t Au from 145 m (18WDRC030)
- 5 m at 3.96 g/t Au from 117 m (18WDRC034)
- 22 m at 1.29 g/t Au from 64 m, including 8 m at 2.3 g/t Au from 64 m (18WDRC039).
Alliance is planning additional drilling for December 2018 to define the limits of gold mineralisation at Shoots 4, 5, and 10 and to test new target areas.
A reverse circulation drilling program is planned at Archer Exploration’s Blue Hills copper–gold project, approximately 240 km north of Adelaide (ASX release 19 November 2018). Twelve holes are planned for a total of 1,800 m at the Hood, Hawkeye, Katniss and Legolas prospects targeting potentially high-grade copper mineralisation.
Ten drillholes have been completed in a maiden drilling program at Auroch Minerals’ Arden project in northern South Australia (ASX release 15 November 2018). All holes intersected sedimentary exhalative (SedEx) zinc and/or copper mineralisation, confirming that previously defined at the Ragless Range prospect and identifying a further two new mineralisation horizons over 3 km of strike, which remain open in all directions. The new discoveries have significantly increased the potential scale of the SedEx base metal system. Best results from the Ragless Range drilling include:
- 8.15 m at 7.52% Zn and 0.02% Pb from 57.65 m, including 3.65 m at 15.47% Zn and 0.02% Pb; and 8 m at 1.29% Zn and 0.02% Pb from 81.84 m (RRDD-007)
- 5.5 m at 1.09% Zn and 0.03% Pb from 147 m (RRDD-005)
- 2 m at 1.45% Zn and 0.12% Pb from 217 m (RRDD -008).
A single 300 m stratigraphic hole was drilled at Kanyaka prospect, intersecting the same stratigraphy identified at the Ragless Range prospect, but individual units were found to be significantly thicker. Similar sulfide-bearing horizons were intersected at or near unit contacts and basal Woodendinna Dolomite, and were shown to be only weakly anomalous in zinc. In contrast to Ragless Range, the limestone units (currently undefined) were observed to contain trace disseminated chalcopyrite, which is also present in sporadic calcite veinlets that occur within the limestone. These units are being prepared for analysis. Best copper intercepts include:
- 2.8 m at 1.33% Cu from 0 m; 5.6 m at 0.50% Cu from 17.4 m (KNDD-002).
Following BHP’s iron oxide – copper–gold (IOCG) discovery 65 km southeast of Olympic Dam, Auroch announced that it had lodged applications for two exploration licences in the Lake Torrens region (ASX release 28 November 2018). With a combined area of 1,622 km2, the application areas are considered highly prospective for IOCG mineralisation, lying 50 km to the east of the BHP discovery. Auroch is excited to have secured such a large area in what is currently one of the most exciting exploration regions in Australia.
Following shareholder approval, BHP Billiton Limited and BHP Billiton Plc have changed their names to BHP Group Limited and BHP Group Plc, respectively, effective 19 November 2018 (ASX release 20 November 2018).
BHP has confirmed a potential new IOCG mineralised system 65 km southeast of Olympic Dam (ASX release 27 November 2018). Discovered as part of its ongoing copper exploration program, four drillholes totalling 5,346 m intersected IOCG-style copper, gold, uranium and silver mineralisation. Downhole mineralisation intercepts range from 0.5 to 6.0% Cu associated with gold, uranium and silver. Results include:
- 124.5 m at 0.52% Cu, 0.48 g/t Au, 85 parts per million (ppm) U and 3.37 g/t Ag from 936 m (AD 22)
- 425.7 m at 3.04% Cu, 0.59 g/t/ Au, 346 ppm U and 6.03 g/t Ag from 1063 m, including 180 m at 6.07% Cu, 0.92 g/t Au, 401 ppm U and 12.77 g/t Ag from 1,070 m (AD 23)
- 406 m at 0.66% Cu, 0.35 g/t Au, 266 ppm U and 2.09 g/t Ag from 848 m (AD 24)
- 77 m at 2.11% Cu, 0.54 g/t Au, 327 ppm U and 2.94 g/t Ag from 1,193 m (AD 25).
With exploration still in an early stage there is insufficient information to assess the size, quality and continuity of the mineralisation. BHP is evaluating and interpreting the results and planning further drilling in early 2019.
The latest drilling campaign undertaken at Boss Resources’ Honeymoon uranium project has been successfully completed ahead of schedule and within budget (ASX release 5 November 2018). Drilling was concentrated on the East Kalkaroo area, located approximately 3–10 km from the Honeymoon uranium mine where two new zones of mineralisation have been identified in channel limbs of northeast–southwest and broadly east–west orientation, respectively. Based on regional airborne electromagnetic data, Boss has interpreted the limbs as extensions of the same Tertiary-aged Yarramba Paleochannel that hosts the Honeymoon uranium deposit. Best results include:
- 3.5 m at 829 ppm pU3O8, grade x thickness (GT) 2,902 from 119 m (BIF0204)
- 2.0 m at 568 ppm pU3O8, GT 1,136 from 124.75 m (BIF0186)
- 2.75 m at 428 ppm pU3O8, GT 1,177 from 109.25 m (BIF0198)
- 2.25 m at 278 ppm pU3O8, GT 626 from 113.50 m (BIF0207)
- 2.25 m at 274 ppm pU3O8, GT 617 from 122.25 m (BIF0206).
A mineralised trend that appears to be 190 m across at its widest point has been identified in Target area 1 situated at the easternmost edge of the Honeymoon mining licence. Its location suggests an extension of the known mineral resource in an orientation different to the currently recognised east–west trend at Honeymoon.
Havilah Resources released its 2018 annual report in an ASX release on 1 November 2018. The future focus is the ongoing implementation of its ‘Copper Strategy – Enhanced by Cobalt’ with several programs planned around key assets including Mutooroo, Kalkaroo and Central Curnamona.
At the Mutooroo Cu–Co–Au deposit, resource expansion and resource conversion drilling programs are proposed along with further metallurgical studies to support the prefeasibility study. Mutooroo lies within Havilah’s defined Mutooroo Copper Cobalt District which hosts several priority drill targets, including Sidewinder, Viper and Taipan prospects. A resource definition drilling program and ground electromagnetic survey is proposed for the Scorpion prospect in the coming year.
At Kalkaroo, one of Australia’s largest undeveloped open pit Cu–Co–Au deposits on a copper equivalent basis, Havilah is continuing metallurgical work to update the draft initial prefeasibility study to ensure the full potential of the project is identified. This will include addressing the value-adding options relating to improved gold recoveries in oxide ores and capturing cobalt value in the pyrite concentrate.
Central Curnamona exploration will target multiple prospects in the vicinity of Kalkaroo where mineralisation is hosted within a regionally persistent gold and base metal (Cu–Co–Au–Pb–Zn–Mo) mineralised horizon that extends for over 200 km along strike. Prospects include Kalkaroo South, North Dome, Croziers and Bassanio.
At the Grants iron ore basin project, SIMEC Mining will undertake drilling as part of its due diligence investigation of the commercialisation potential of the Grants iron ore basin.
Leigh Creek Energy
Leigh Creek Energy provided an update on its pre-commercial demonstration facility of the Leigh Creek energy project (ASX release 15 November 2018). The process of developing the gasifier is continuing and has seen:
- pre-commercial demonstration operation for 35 days continuing the initial gas flows
- increased gasifier pressure and temperature
- plant and equipment operating as designed.
The company is planning to inject an approved fuel source that will reignite to provide an additional heat source to accelerate the gasifier development process.
Magnetite Mines announced two Joint Ore Reserves Committee (JORC) 2012 compliant resource updates:
- Razorback premium iron project – total mineral resource estimate remains unchanged at 2,732 million tonnes (Mt) of 18.2% Fe (ASX release 12 November 2018)
- Ironback Hill – total inferred resource estimate remains unchanged at 1.2 billion tonnes at 23.2% Fe (ASX release 20 November 2018).
The company’s combined total mineral resources inventory in the Braemar Region stands at 3.9 billion tonnes at 19.7% Fe head grade (ASX release 20 November 2018).
Marmota has reported further success at its Aurora Tank gold project located in the vicinity of the Challenger gold mine, now in care and maintenance (ASX release 14 November 2018). Results from the September 2018 drilling include the best ever gold drilling intersection of 4 m at 72 g/t Au from 36 m in 18ATRC104. This new intersection is located in a zone some 200 m to the west of the previous best intersection of 4 m at 40 g/t (drillhole 17AT021) and is open in a number of directions. Other intersections include:
- 8 m at 3.6 g/t Au from 56 m, including 4 m at 6.6 g/t Au from 56 m (18ATRC120)
- 8 m at 2.1 g/t Au, including 4 m at 4.0 g/t Au from 52 m (18ATRC119).
Marmota has attributed a recent biogeochemical tree sampling program as assisting in locating the latest drillholes.
OZ Minerals has entered into a formal Transmission Connection Agreement with ElectraNet to construct a new transmission line and associated high voltage infrastructure to connect Prominent Hill under a build, own, operate and maintain agreement to the South Australian grid power supply. The new transmission line will replace the existing BHP facility in 2020 (ASX release 30 October 2018).
OZ achieved a major milestone in November for the Carrapateena Province exploration program with the release of a maiden mineral resource estimate for the Fremantle Doctor deposit of 104 Mt at 0.7% Cu, 0.5 g/t Au and 3 g/t Ag for 800,000 t of copper, 2 million ounces (Moz) of gold and 10 Moz of silver contained (ASX release 12 November 2018). The estimate is based on data from 22 drillholes for a total of 31,587 samples in mineralised domains. The deposit lies just over 2 km from the Carrapateena ore body and will be considered as an adjunct development to the Carrapateena project.
OZ also released an updated mineral resource statement for Prominent Hill of 130 Mt of copper, grading at 1.1% Cu, 0.6 g/t Au and 3 g/t Ag for 1,500 kilotonnes (kt) of copper, 2.4 Moz gold and 12 Moz silver, plus a gold resource of 20 Mt at 1.2 g/t Au which will see mine life extended to 2030 (ASX release 12 November 2018).
Both the total copper mineral resource and total ore reserve represent a decrease of 7% while total gold mineral resource was down 4% from the previous mineral resource estimate released in November 2017. These decreases are primarily due to mining depletion from both the open pit and underground. A 2% increase in underground ore reserve after mining depletion has extended the Prominent Hill mine life by another year, enabling the expected underground production rate of 3.5-4.0 Mt per annum from 2019 to continue into 2030.
Underground ore reserve tonnes and contained metal remain in line with the prior year, with open pit and underground mining depletion partially offset by increases in underground ore reserves. Improved geological confidence from diamond drilling activity through the year has resulted in proved underground ore reserves increasing by 50% to 28 Mt.
OZ has restated the 2017 Carrapateena mineral resource and ore reserve estimates with an update expected in the first quarter of 2019, i.e. total mineral resource 134 Mt at 1.5% Cu, 0.6 g/t Au, 6.5 g/t Ag for 1,970 kt of copper, 2,570 thousand ounces (koz) of gold and 28 Moz of silver. Total ore reserve is 79 Mt of copper at 1.8% Cu, 0.7 g/t Au and 8.5 g/t Ag for 1,400 kt of copper, 1,800 koz of gold and 22 Moz of silver.
Adelaide-based Petratherm released its third quarter 2018 activities report announcing that it had completed a 42 aircore drilling program at the Corunna project in the southern Gawler Craton (ASX release 14 September 2018). The drilling tested five structural targets defined in a ground magnetic survey completed in September. Best results from Area 1 include:
- 12 m at 20.0 g/t Ag, 0.8% Pb and 0.2% Zn from 20 m (CO18AC10)
- 4 m at 13.0 g/t Ag, 0.6% Pb and 0.3% Zn from 32 m (CO18AC11)
- 20 m at 12.0 g/t Ag, 0.3% Pb and 0.2% Zn from 12 m (CO18AC12)
- 12 m at 9.0 g/t Ag, 0.5% Pb and 0.3% Zn from 20 m (CO18AC17).
The results extend the zone of Ag–Pb–Zn anomalism previously defined by Musgrave Minerals across a 300 x 500 m zone which remains open in all directions (ASX release 31 October 2018).
An exploration licence has been secured in the highly prospective Bendigo Gold Zone in Victoria (ASX release 22 November 2018). The licence covers the northern portions of the historic Wedderburn Goldfield and extends over areas of shallow cover with little previous exploration.
Renascor Resources has entered into a strategic partnership agreement with highly respected international engineering, procurement and construction contractor Royal IHC Australia to accelerate the development of its Siviour Graphite Project – one of the world’s largest undeveloped graphite deposits (ASX release 5 November 2018). Siviour has a mineral resource estimate of 80.6 Mt at 7.9% total graphitic carbon (TGC) for 6.4 Mt of contained graphite.
Under the terms of the agreement the Netherlands-based Royal IHC in association with Australian engineering firm Wave International will assist Renascor to deliver the Siviour definitive feasibility study, providing specialist skills in mining, metallurgy and innovative engineering solutions. Royal IHC has committed $1 million to undertake these early project works.
The recently completed definitive feasibility study drilling intersected additional near-surface high-grade graphite. First assay results have been released (ASX release 7 November 2018) and some of the best results include:
- 25 m at 14.0%TGC from 12 m (18SIVAC145)
- 33 m at 8.9% TGC from 11 m (18SIVAC155)
- 24 m at 10.2% TGC from 26 m (18SIVAC171)
- 24 m at 9.5% TGC from 8 m (18SIVAC160)
- 23 m at 9.4% TGC from 8 m (18SIVAC158).
The results support continuity of widespread, high-grade graphite within the Siviour indicated resource and Renascor plans to include them in an updated mineral resource estimate and reserve determination.
Further assay results released in an ASX release on 14 November 2018 support continuity of widespread, high-grade graphite within the indicated resource. Results include:
- 35 m at 13.2% TGC from 26 m (18SIVAC216)
- 24 m at 14.2% TGC from 11 m (18SIVAC184)
- 37 m at 9.40% TGC from 45 m (18SIVAC187)
- 27 m at 12.4% TGC from 16 m (18SIVAC205)
- 39 m at 8.40% TGC from 11 m (18SIVAC202)
- 25 m at 12.8% TGC from 11 m (18SIVAC195)
- 38 m at 8.20% TGC from 17 m (18SIVAC189)
- 22 m at 11.5% TGC from 12 m (18SIVAC197)
- 22 m at 12.1% TGC from 14 m (18SIVAC209)
- 38 m at 7.30% TGC from 41 m (18SIVAC211).
Another milestone in the development of the Siviour graphite project was achieved with the completion of 100% acquisition of Ausmin Development, which holds the rights to the project (ASX release 22 November 2018).
Independent tests have confirmed the ability to upgrade Siviour graphite concentrates to +99.95% TGC using a more environmentally friendly and cost-efficient caustic roasting purification process (ASX release 28 November 2018).
The western Gawler Craton is a key exploration focus going forward for Western Areas in light of the farm-in agreement signed with Iluka Resources in July 2018 (ASX release 31 July 2018). Western Areas can acquire up to 75% of the base metal and precious metal rights as well as basement-hosted mineral and rare earth elements over ground which is contiguous with its own tenure giving it almost 100% coverage of the highly prospective Fowler Domain.
Having already completed a 217 hole drilling program,149 line km of moving loop electromagnetic ground surveys and identified a strong pipeline of targets, the company will be further ramping up exploration in financial year 2019. A regional-scale SkyTEM airborne electromagnetic survey has been completed and an integrated series of belt-scale exploration campaigns are planned (ASX release 22 November 2018).