Orion Gold NL
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Prieska Zinc-Copper Project (South Africa)

Advanced Zn-Cu project being fast tracked to feasibility


  • Major infrastructure in place (power, water, road/rail access, accommodation)
  • World class orebody, well understood
  • Recorded as one of world’s top 30 VMS deposits
  • Production of over 430,000 tonnes of copper and more than 1 million tonnes of zinc
  • Proven metallurgical process to produce premium product

The PC project is located 270 kilometres south-west of Kimberley (the regional capital) in the Northern Cape province. Importantly, the project has access to significant local and regional infrastructure, with mine infrastructure including a regional power grid feed, bitumen access roads, access to a bulk, treated water supply and a 1,900 metre landing strip. Several large commercial wind and solar generation projects are operational in the surrounding area and the mine is located just 48 kilometres from a railway siding at Groveput with an open-access railway line connecting the site to the world-class export port of Saldanha Bay.

In November 2015 the Company announced the signing of a binding term sheet giving Orion the right to acquire the unlisted company, Agama Exploration & Mining (Pty) Ltd (Agama), a South African registered company which through its subsidiary companies, ultimately holds an effective 73.33% interest in the PC Project and the Marydale gold project (Option). The commercial terms were revised in May 2016 and are detailed below. The projects have a well established Broad Based Black Economic Empowerment (BBBEE) ownership structure (26.66% ownership) in place with strong local partners.  On 29 March 2017, the Company completed the acquisition of 100% interest in Agama, taking an important step in its strategy of base metal development.















The PC Project cover the historical Prieska Copper Mine, which was operated by Anglovaal Limited between 1971 and 1991. During this time the mine produced over 430,000 tonnes of copper and more than 1 million tonnes of zinc from an underground operation based on an initial drilled reserve(3) of 47Mt grading 1.74% copper, 3.87% zinc, 8g/t silver, 0.4g/t gold and 30% pyrite. The operation was a significant financial success for its owners, returning ZAR2.64 per share (US$1.16 in money of the time) in dividend yields for an investment of ZAR0.5 per share (US$0.70) by the shareholders.

Mining ceased in 1989, with milling ceasing in 1991.  The site was closed and rehabilitated in 1991. The premature closure of the mine was influenced by an early operating decision by the owners to focus on maximising dividend yields, rather than investing further in underground capital development to extend mine life. The decision was influenced by uncertain economic and political environment in South Africa in the mid-1980s.

The underground development and regional infrastructure and services in place at the mine is estimated by Orion to have significant replacement value, which will assist in the feasibility and economics of any potential redevelopment of the mine. The underground mine is accessed via an 8.8 metre diameter concrete lined vertical shaft to a depth of 1,024 metres. Three separate ramp declines (6.5 metres by 3.8 metres) have been developed to access the deepest ore at a vertical depth of 1,140 metres. The mineralisation lies in a synformal structure and the target lies in the keel and upturned limb of the syncline, above 1,200 metres.

2. Source of information in this section: Mine records. 

3.Note – this is not a JORC Compliant figure, source Prieska Copper Mines Ltd Annual Report 1970.

Orion’s Due Diligence and Confirmatory Drilling

The terms of the Option enables Orion to continue to conduct comprehensive due diligence, including geophysics, in-fill and confirmatory drilling and feasibility studies in advance of a decision to exercise the Option and to advance discussions with prospective investors interested in financing and/or joint venture participation in the acquisition.

Since signing of the Option the Company has progressed extensive due diligence investigations including:

  • Legal title opinion by Japie Van Zyl Attorneys in South Africa has confirmed good standing of the Prospecting Rights of the PC Project and the Marydale project, freehold title to certain properties at PC and servitude rights for usage of all land required to operate PC if a Mining Right is granted.
  • Paul Matthews, a geologist and Competent Person under the JORC Code, has undertaken extensive review of historical geological records, capturing and recording all information to evaluate the geological potential and has signed off on the +105 Level and Deep Sulphide Exploration Targets including compilation of information required under the JORC Code (refer ASX Release 18 November 2015).
  • A comprehensive review of environmental conditions, mining infrastructure, engineering design and costing for potential future mine development to +-30% accuracy levels (normally applied at the Scoping Study level) has been carried out by a team of over 10 engineers and scientists under the supervision of the METS Group and Shaft Sinkers, who are industry leaders in planning and executing primary mine development.
  • METS made use of specialist sub-contractor groups to evaluate open pit mining, underground mining, mineral processing and environmental conditions.
  • Drilling has commenced to firm up on the expectations of the Exploration Target and advance toward JORC compliant resources.

As part of its due diligence process, Orion has digitally captured, validated and modelled all available project drilling data, from hard-copy sources. This work has enabled the Company to calculate Exploration Targets for near surface mineralisation comprising both oxide, supergene and primary sulphide material to a depth of 100 metres which is potentially accessible via an initial open pit (+105 level Exploration Target) and an Exploration Target for the deeper sulphide mineralisation identified by historic drilling (Deep Sulphide Exploration Target) (refer Table 1 and ASX Release 18 November 2015).

The Exploration Target is based on 182 historical drill intersections, which can be relied on for width and depth of mineralisation, while 88 historical drillholes provide information on grade of mineralisation (Figure 14 and 15). While the data has shortcomings due to loss of some historic records, which prevent estimation of JORC 2012 compliant resources, the Company is encouraged by the assessment by its Competent Person that limited infill and confirmatory drilling may be sufficient to establish JORC 2012 compliant resource estimates. The historic data and mine records also provide important information for preliminary mine design and selection of mining methods to advance scoping studies.


PC Project – Exploration Targets
Area Tonnage Range Cu range (%) Zn range (%)
+105 Level 3,000,000 – 4,500,000 1.0 – 1.6 1.3 – 2.0
Deep Sulphide 7,000,000 – 11,000,000 1.2 – 1.8 3.9 – 5.9

Table 1:   Exploration Targets at the PC Project.  Detail and supporting information relating to these Exploration Targets is contained in the ASX Release of 18 November 2015.


The current drilling program at the +105 Level Exploration Target. is designed to confirm, in-fill and extend the historical drilling and targets mineralisation that would be amenable to extraction via open pit  (Table 1). The latest drilling results can be found in our Announcements section. Best results at this time include:

  • 22m at 10.8% Zn, 1.38% Cu and 0.3g/t Au from 57m, including:

7m at 17.8% Zn and 1.41% Cu (OCOR016);

  • 20m at 8.58% Zn, 2.21% Cu and 0.3g/t Au from 48m, including:

17m at 9.98% Zn and 2.01% Cu (OCOR023); and

  • 12m at 4.14% Cu, 1.89% Zn and 0.29g/t Au from 57m, including:

3m at 7.4% Cu and 4.34% Zn (OCOR017).



Commercial Terms

Acquisition - Agama Exploration & Mining (Pty) Ltd (South Africa)

The Company completed the acquisition of 100% interest in Agama Exploration & Mining (Pty) Ltd  (Agama) on 29 March 2017.  Agama holds an effective 73.33% interest in the Prospecting Rights over the historic Prieska Copper Mine (PC) and the nearby Marydale project.

The effective acquisition price was ZAR88.5 million (~A$8.9 million) = ZAR66 million cash and ZAR22.5 million in Orion shares.  Each share issued will have an attached unlisted option, exercisable at a 100% premium to the share issue price and expiring on the date which is 24 months following the date of issue of the unlisted option.  The PC project has also secured ZAR30 million facility to partly fund a feasibility study.

Refer ASX releases 30 March 2017 and  29 March 2017 for further information on the completed acuqisition.