Wrap Text
Prieska Crown Pillar +105 Level Mineral Resource increases to 2.3Mt @ 1.7% Cu and 1.6% Zn ahead of
Trial Mining
Orion Minerals Limited
Incorporated in the Commonwealth of Australia
Australian Company Number 098 939 274
ASX share code: ORN
JSE share code: ORN
ISIN: AU000000ORN1
Prieska Crown Pillar +105 Level Mineral Resource increases to 2.3Mt @ 1.7% Cu and 1.6% Zn ahead of
Trial Mining
Near-surface resource supports early production strategy with start of trial mining imminent
- Updated Mineral Resource estimate completed for the +105m Level Crown Pillar Block at the
Prieska Copper-Zinc Project in South Africa, incorporating all 2022 drilling data.
- Updated +105m Level Mineral Resource: 2.3Mt @ 1.7% Cu and 1.6% Zn including an Indicated
Resource of 1.9Mt @ 1.82% Cu and 1.70% Zn.
- Significant increase in Oxide Resource, based on new and more robust interpretations.
- Prieska’s total Mineral Resource, reported and classified in accordance with the JORC Code
(2012), increases to 31Mt grading 1.2% Cu and 3.6% Zn.
Orion’s Managing Director and CEO, Errol Smart, commented:
“Our strategy to bring the Prieska Copper-Zinc Mine back into production is now rapidly gaining
momentum, with the completion of this updated Mineral Resource for the near-surface, +105 Resource
Block, outlining a very attractive early mining opportunity at this fully permitted mine.
“The supergene sulphide, Indicated Resource, with a grade of 2.6% copper, is a compelling focus for our
early mining strategy. This resource block is accessed from existing underground development via a short
ramp, allowing trial mining to commence in the coming weeks. Ore sourced from the trial mining will be
used for metallurgical optimisation tests and for the detailed design of an initial processing plant at Prieska.
“Discussions with metallurgical processing and engineering groups interested in offering processing facilities
under Build-Own-Operate-Transfer arrangements are also underway.
“The trial mining phase, metallurgical process optimisation and a resultant updated Bankable Feasibility
Study is fully funded with a total of ZAR370 million available from our IDC and Triple Flag funding facilities. A
first draw-down call for ZAR167 million was made from this facility in the past week. Orion is now getting
ready to embark on its transformation to an operating mining company!”
Orion Minerals Limited (ASX/JSE: ORN) (Orion or Company) is pleased to advise that it has taken another
key step in its early mining strategy at the Prieska Copper-Zinc Project (Prieska Project) in the Northern Cape,
South Africa with the completion of an updated Mineral Resource Estimate (MRE) for the near-surface +105
Level Crown Pillar comprising Indicated and Inferred Resources of 2.3Mt grading 1.7% Cu and 1.6% Zn
(Figure 1, Table 1).
The updated MRE for this shallow portion of the Prieska deposit represents a robust focus for the trial mining
program scheduled to commence in the next few weeks. The updated MRE is based on a successful drilling
program completed in 2022.
The +105 Level Crown Pillar is located in close proximity to existing underground infrastructure and can be
readily accessed, allowing trial mining activities to commence immediately with all required permits and
funding now in place.
This program will generate key metallurgical and other data that will assist with process plant design and
also feed into an updated Bankable Feasibility Study (BFS) for the Early Production Strategy at Prieska.
The updated MRE for the +105 Level Crown Pillar brings the total Indicated and Inferred Mineral Resource
including the Deep Sulphide Mineral Resource (refer ASX/JSE release 18 December 2018)1 of the Prieska
Project to 31Mt grading 1.2% Cu and 3.6% Zn (Table 2).
Updated +105m Level Crown Pillar Mineral Resource
The geological wireframe and resource estimate for the +105 Level Mineral Resource have been updated
to include additional drill data from the 2022 drill campaign. There has also been a review of the modelling
of metallurgical zonation in all areas of the +105m Level Mineral Resource with refinements applied where
appropriate (Figure 2).
Additional drilling and changes to the resource model successfully increased the total +105m Level Mineral
Resource from 1.8Mt grading at 1.5% Cu and 2.0% Zn (refer ASX/JSE release 15 January 2019) to 2.3Mt
grading 1.7% Cu and 1.6% Zn, including Indicated Resources of 1.9Mt grading 1.82% Cu and 1.70% Zn and
Inferred Resources of 0.4 Mt @ 1.0% Cu and 0.8% Zn.
The +105m Level Mineral Resources shown in Table 1 are based on drilling data available for the Prieska
Copper Zinc Mine (previously Repli) Mining Right NC30/5/1/2/2/10138MR. The Mineral Resources are
reported in accordance with the JORC Code (2012), with supporting information provided in Appendix 1.
Table 1: Global Indicated and Inferred Mineral Resource statement for the +105m Level Resource Block of the Prieska Project.
Cu Cu Zn Zn
Classification Mineralised Zone Tonnes
(tonnes) (%) (tonnes) (%)
HW Oxide 200,000 1,000 0.48 2,000 0.90
Oxide 490,000 4,000 0.81 4,000 0.73
Indicated Supergene Sulphide 1,100,000 28,000 2.58 22,000 2.06
Hypogene 120,000 1,000 1.23 4,000 3.78
Total 1,900,000 34,000 1.82 32,000 1.70
HW Oxide 30,000 100 0.4 300 1.0
Oxide 300,000 3,000 1.0 2,000 0.8
Inferred Supergene Sulphide 60,000 1,000 1.4 300 0.6
Hypogene 20,000 100 0.8 100 0.4
Total 400,000 4,000 1.0 3,000 0.8
+105m Level Mineral Resource Total 2,300,000 38,000 1.7 35,000 1.6
Note: +105m Level Mineral Resource bottom cut-off = 0.3% Cu.
Tonnes are rounded to second significant figure, which may result in rounding errors.
1
Mineral Resource reported in ASX release of 18 December 2018: “Landmark Resource Upgrade Sets Strong Foundation” available to the public on
www.orionminerals.com.au/investors/market-news. Competent Person Orion’s exploration: Mr. Errol Smart. Competent Person: Orion’s Mineral Resource:
Mr. Sean Duggan. Orion confirms it is not aware of any new information or data that materially affects the information included above. For the Mineral
Resources, the company confirms that all material assumptions and technical parameters underpinning the estimates in the ASX release of 18 December
2018 continue to apply and have not materially changed. Orion confirms that the form and context in which the Competent Person’s findings are
presented here have not materially changed.
Figure 1: Longitudinal schematic section showing the historically mined area and the +105m Level Mineral Resource at the Prieska
Project, with the Deep Sulphide Mineral Resource.
Figure 2: View showing the +105m Level Mineral Resource with the Supergene Sulphide Zone in red, the Hypogene Sulphide Zone in
purple, the main Oxide Zone in yellow and the HW Oxide Zone in green. The area between the main Oxide and Supergene Sulphide
zones is a leached (clay) zone (blue) with insignificant Cu and Zn values and is excluded from the Mineral Resource. Brown represents the
interpreted overburden.
Since the previous +105m Level Mineral Resource (refer ASX/JSE release 15 January 2019), 14 holes
comprising 918m were successfully drilled to intersect supergene sulphide mineralisation (refer ASX/JSE
release 11 July 2022). A further five holes were drilled and abandoned due to poor ground conditions and
unacceptable core loss.
In compliance with ASX Listing Rule 5.8.1, the following sections present a summary of all information
material to understanding the reported Mineral Resource estimates:
Geology & Geological Interpretation
The Prieska Cu-Zn Deposit is a volcanogenic massive sulphide (VMS) deposit which is situated in the
southernmost exposures of the north-northwest trending Kakamas Terrain, which forms part of the Mid-
Proterozoic Namaqualand Metamorphic Complex. The deposit is hosted by the Copperton Formation of
the Areachap Group.
The structural sequence at the mine consists of a footwall Smouspan Gneiss Member, Prieska Copper Mines
Assemblage, which hosts the sulphide mineralisation, and the hangingwall Vogelstruisbult Gneiss Member.
The +105m Level Resource occurs above the upper limit of the historically mined Prieska Cu-Zn Deposit at
approximately 105m depth below surface, up to surface. It has a strike length of approximately 1km and
thicknesses vary between 1.5m and 23m.
The +105m Level Resource Block comprises six defined zones (Figure 2).
• Haematite-goethite-quartz oxide zone (gossan) from surface to approximately 33m.
• Clay (kaolinite)/leach zone developed in places below 33m.
• Chalcocite dominant supergene sulphide zone between approximately 42m and 70m.
• Mixed supergene-hypogene sulphide zone between approximately 70m and 90m below surface. This
has a relatively sharp contact with the underlying hypogene massive sulphides.
• Hypogene sulphide zone consisting of the unaltered, fresh massive sulphides.
• A separate zone of elevated Cu and Zn values in the oxides (where there is adequate drilling
information) in the hangingwall to the main +105m Level crown pillar is present in the northwest of the
deposit for approximately 300m strike. The zone converges with the main zone towards the southeast.
Four zones have been defined for inclusion as part of the +105m Level Mineral Resource and these are
referred to as the HW Oxide Zone, the Oxide Zone, the Supergene Sulphide Zone and the Hypogene Zone.
Estimation Methodology
The wireframe of the +105m Level Block was constructed for Mineral Resource estimation utilising Cu%
values greater than or equal to 0.3% and Zn% values greater than or equal to 0.6%. Surfaces were created
to subdivide the mineralised zone into the various domains.
Samples were composited to 1m. The exceptionally high assay values for all variables were capped to
selected thresholds using the Parker methodology. A block model with cells of 40m X by 40m Y by 5m Z was
used for the +105m Level Block with a sub-cell size of 1m x 1m x 1m.
Data from the Oxide and HW Oxide zones were analysed together. Data from the Supergene Sulphide and
Hypogene zones were analysed together with an interpreted ‘soft boundary’. These groupings together
with the Leach Zone were analysed independently to ensure that the plane for estimation had an optimal
orientation. Following a spatial analysis, the composite data was used to estimate the block grades using
ordinary kriging (OK).
For the oxide domain, neighbourhood analysis resulted in an optimum search neighbourhood of 100m x
4m for local block estimation, corresponding to the variogram range. The second and third pass estimates
were calculated from the pass 1 OK estimates using a moving average technique with the search radii
increased to 200m / 7m and 400m / 20m respectively. 51% of blocks were estimated by the first pass local
block estimation.
For the supergene sulphide and hypogene domain, neighbourhood analysis resulted in an optimum search
neighbourhood of 100m x 7.2m for local block estimation, corresponding to the variogram range. The
second and third pass estimates were calculated from the pass 1 OK estimates using a moving average
technique with the search radii increased to 200m / 7m and 400m / 20m respectively. 80% of blocks were
estimated by the first pass.
Bulk densities (t/m3) were determined using the water displacement method. Due to poor rock quality the
density data in the Oxide Zone was sparse, with only 48 samples available. There are 203 density
measurements in the Supergene Sulphide Zone. The entire sample (normally 1m length) was measured, or
where the formation was highly fractured, a shorter length was measured.
Local block estimates of density were produced using ordinary kriging in areas of close-spaced sampling.
A second pass with longer search radii was utilised and the remaining blocks were populated using grid
filling.
DatamineTM was utilised to create a block model and measure individual block volumes within each zone
and these data were imported into IsatisTM for further geostatistical analysis.
The HW Oxide, Oxide, Supergene Sulphide and Hypogene zones are reported separately in the Mineral
Resource statement. The clay/leach zone is all below the 0.3% Cu cut off.
Resource Classification
The geology of the two zones making up the +105m Level Mineral Resource is relatively uncomplicated,
and the key issues relate to the delineation of the domain boundaries (not geology).
The Oxide Zone is classified as both Inferred and Indicated Mineral Resources. The geological model is
defined to a reasonable level and there is sufficiently accurate data to produce local block estimates using
ordinary kriging, albeit there is a limited number of samples in some areas, especially in the southeast where
surface drilling access was restricted by the presence of sinkholes. There is a high level of uncertainty
associated with the zonal estimation of density due to a low number of samples as well as possible
inaccuracies associated with core loss. Two collapse zones (related to collapse in the sinkhole) have been
interpreted up-dip based on drilling information from the Supergene Sulphide zone.
The Supergene Sulphide and Hypogene Zones are predominantly classified in the Indicated category with
some small areas in the Inferred category. The geological model is defined to a reasonable level and there
is sufficiently accurate data coverage to produce local block estimates using ordinary kriging. In parts of
the Supergene Sulphide Zone there are sufficient data for reasonably accurate local block estimates of
grade (~80% of blocks populated by 1st pass kriging). Local block estimation for density with reasonable
accuracy was possible. The kriging performance parameters, e.g. slope of regression, together with an
assessment of the areas of blocks that were populated by 1st pass kriging, were utilised to make a distinction
between the Indicated and Inferred classifications.
The results conform to the view of the Competent Person.
Changes in +105m Level Mineral Resources
Given the changes in the interpretation of mineralised domains, a direct comparison of updated and
previous (2019) resource figures is difficult. However, the total tonnes (Indicated and Inferred classification
categories) are 2.3M which is an increase from 1.8M tonnes in 2019. The Cu tonnes have increased from
27,000t in 2019 to 38,000t and the Zn tonnes have slightly increased by 300t.
The increase in overall tonnes can be largely attributed to the extension of the interpreted crown pillar
mineralised zone towards the southeast to where it intersects the sidewall of a sinkhole. The more
comprehensive interpretation of the mineralised zone in the hangingwall to the main crown pillar
mineralisation also contributes significantly to this increase in tonnage (and to that of the oxide tonnage).
The changes in the interpretation of the bottom of the oxide zone (particularly in the northwest) had a
significant positive impact on the oxide tonnage.
The increase in Cu tonnes can be largely attributed to higher grades in the southeast of the supergene
sulphide zone from the 2022 drilling, the extended interpretation of the crown pillar mineralisation to the
southeast, and the changes in the interpretation of the bottom of the oxides.
Metallurgy
Ore extracted from the +105 mineralised zone was previously treated using froth flotation metallurgical
process by Prieska Copper Mine. Mixed oxide, supergene and hypogene sulphide ore was successfully
treated by froth flotation to produce separate copper and zinc concentrates during the 1980’s2.
Limited flotation test work was carried out on the oxide mineralisation however, results were unsuccessful.
The oxide mineralisation has a reasonable prospect for eventual economic extraction as it occurs close to
the surface and treatment of this type of ore by means of leaching is well-known in the industry.
Plans are underway for additional drilling of oxides in 2023 Q3, to collect a more representative sample for
further metallurgical test work.
2 Broekman B.R. and Penman D.W. The Prieska Experience: Flotation Developments in Copper-Zinc Separation. The Journal of South African Institute of
Mining Metallurgy, volume 91, no. 8, Aug 1991, pp 257-265.
Cut-off Grades & Mining Methods
The +105m Level Mineral Resource is reported above a 0.3% Cu cut off. This corresponds with the wireframe
modelling and is similar to that used in many open cast mining deposits worldwide. Whilst previously open
pit mining was evaluated for the deposit (refer ASX/JSE release 26 May 2020), underground mining for the
+105 Level Resource is now being considered as an optimisation alternative, with underground trial mining
to commence in coming weeks (Figures 3 and 4).
Figure 3: Access ramp, reef drives and raises in +105 trial Mining Project.
Figure 4: Conceptual Layout of +105 Resource Drift & Fill Mining.
Future Work
An infill drilling program of approximately 1,700m on the Oxide Resource to provide a further upgrade in
confidence and additional metallurgical information is planned for Q3, 2023 (Figure 5). However, this is not
critical to the current early mining BFS studies. Apart from this infill drilling of the Oxide Resource, no
additional drilling is planned, for mining of sulphide ore, before the completion of the updated BFS in late
2023. Grade control drilling on a closely spaced grid will be executed during the operational phase of
mining.
Figure 5: Longitudinal Section of the Crown Pillar +105 Level Mineral Resource area with existing drill hole coverage and planned Oxide
Infill drill intercepts.
Total Prieska Project Mineral Resource
The Deep Sulphide Mineral Resource of the Prieska Deposit, which was announced in December 2018 (refer
ASX/JSE release 18 December 2018), combined with the +105m Level Mineral Resource is summarised in
Table 2 below.
Table 2: Global Mineral Resource for the combined +105m Level and Deep Sulphide Mineral Resources of the Prieska Project.
Cu Cu Zn Zn
Resource Classification Tonnes
(tonnes) (%) (tonnes) (%)
Indicated 19,000,000 220,000 1.17 670,000 3.60
Deep Sulphide Resource
Inferred 10,000,000 120,000 1.1 420,000 4.1
Indicated 1,900,000 34,000 1.82 32,000 1.70
+ 105m Level Resource
Inferred 400,000 4,000 1.0 3,000 0.8
Total Indicated 20,000,000 250,000 1.23 700,000 3.43
Total Inferred 11,000,000 120,000 1.1 420,000 4.0
Grand Total 31,000,000 370,000 1.2 1,100,000 3.6
Notes: Deep Sulphide Resource bottom cut-off = 4% Equivalent Zn; +105m Level Mineral Resource bottom cut-
off = 0.3% Cu.
Tonnes are rounded to second significant figure, which may result in rounding errors.
As part of the updated BFS, Orion now looks forward to the completion of detailed scheduling and mine
design for the +105m Level as part of the Early Production Scenario (refer ASX/JSE release 20 January 2022).
Project Background
The Prieska Project is located in the Northern Cape Province of South Africa, approximately 290km south-
west of the city of Kimberley. The project area encompasses the historical Prieska Copper Mine (PCM). PCM
was profitably operated by Anglovaal as an underground copper and zinc mine, exploiting the Copperton
deposit between 1971 and 1991, processing on average 3Mt per year to produce 1.01Mt of zinc and 0.42Mt
of copper in concentrates (refer ASX/JSE releases 15 November 2017 and 26 May 2020). Run-of-mine ore
was treated by froth flotation to produce separate concentrates of copper and zinc.
Orion is now investigating the establishment of new mining operations targeting the extraction of the
remaining copper-zinc mineralisation at the Prieska VMS deposit.
Orion has delineated a Mineral Resource for the +105m Level and Deep Sulphide Mineral Resources,
classified by a Competent Person and reported in accordance with the JORC Code (2012), amounting to
31Mt grading 1.2% Cu and 3.6% Zn of which, 20Mt grading 1.23% Cu and 3.43% Zn is classified in the
Indicated category.
Trial mining and metallurgical optimisation work are underway, with a revised bankable feasibility study
scheduled for completion in late 2023.
For and on behalf of the Board.
Errol Smart
Managing Director and CEO
25 July 2023
ENQUIRIES
Investors Media JSE Sponsor
Errol Smart – Managing Director & CEO Nicholas Read Monique Martinez
Denis Waddell – Chairman Read Corporate, Australia Merchantec Capital
T: +61 (0) 3 8080 7170 T: +61 (0) 419 929 046 T: +27 (0) 11 325 6363
E: info@orionminerals.com.au E: nicholas@readcorporate.com.au E: monique.martinez@merchantec.com
Competent Person’s Statement
The information in this report that relates to Exploration Results is based on information compiled by Mr Paul Matthews
(Pr.Sci.Nat.), a Competent Person who is a member of the South African Council for Natural Scientific Professionals, a
Recognised Professional Organisation (RPO). Mr Matthews is a full-time employee of Orion. Mr Matthews has sufficient
experience that is relevant to the style of mineralisation and type of deposit under consideration and to the activity
being undertaken to qualify as a Competent Person as defined in the 2012 Edition of the JORC Code. Mr Matthews
consents to the inclusion in this announcement of the matters based on his information in the form and context in which
it appears.
The information in this report that relates to Mineral Resources is based on information compiled by Mr Sean Duggan,
a Competent Person who is a Director and Principal Analyst at Z Star Mineral Resource Consultants (Pty) Ltd. Mr Duggan
(Pr.Sci.Nat) is registered with the South African Council for Natural Scientific Professionals (Registration No. 400035/01),
an RPO. Mr Duggan has sufficient experience that is relevant to the style of mineralisation and type of deposit under
consideration and to the activity being undertaken to qualify as a Competent Person as defined in the 2012 Edition of
the JORC Code. Mr Duggan consents to the inclusion in this announcement of the matters based on his information in
the form and context in which it appears.
Reference to Previous Reports
The Deep Sulphide Mineral Resource was reported in ASX/JSE Release of 18 December 2018: “Landmark Resource
Upgrade Sets Strong Foundation for Development of Prieska Zinc-Copper Project” available to the public on
https://orionminerals.com.au/download/25/market-news-2018/2902/landmark-resource-upgrade-at-prieska-zinc-
copper-project-2.pdf. Competent Person: Mr. Sean Duggan. Orion confirms it is not aware of any new information or
data that materially affects the information related to the Deep Sulphide Mineral Resource included in the original
market announcement. Orion confirms that all material assumptions and technical parameters underpinning the Deep
Sulphide Mineral Resource in the ASX/JSE Release of 18 December 2018 continue to apply and have not materially
changed. Orion confirms that the form and context in which the Competent Person’s findings are presented here have
not been materially modified from the original market announcement.
Disclaimer
This release may include forward-looking statements. Such forward-looking statements may include, among other
things, statements regarding targets, estimates and assumptions in respect of metal production and prices, operating
costs and results, capital expenditures, mineral reserves and mineral resources and anticipated grades and recovery
rates, and are or may be based on assumptions and estimates related to future technical, economic, market, political,
social and other conditions. These forward-looking statements are based on management’s expectations and beliefs
concerning future events. Forward-looking statements inherently involve subjective judgement and analysis and are
necessarily subject to risks, uncertainties and other factors, many of which are outside the control of Orion. Such
forward-looking statements are based on numerous assumptions regarding the Orion's present and future business
strategies and the political and economic environment in which the Orion will operate in the future, which are not
guarantees or predictions of future performance. Actual results and developments may vary materially from those that
may be contemplated or implied by forward-looking statements in this release.
Given these uncertainties, readers are cautioned not to place undue reliance on such forward-looking statements. All
information in respect of Exploration Results and other technical information should be read in conjunction with
Competent Person Statements in this release (where applicable). To the maximum extent permitted by law, Orion and
any of its related bodies corporate and affiliates and their officers, employees, agents, associates and advisers:
• disclaim any obligations or undertaking to release any updates or revisions to the information in this release to
reflect any events, circumstances or change in expectations or assumptions after the date of this release;
• do not make any representation or warranty, express or implied, as to the accuracy, reliability or completeness of
the information in this release, or likelihood of fulfilment of any forward-looking statement or any event or results
expressed or implied in any forward-looking statement; and
• disclaim all responsibility and liability for these forward-looking statements (including, without limitation, liability for
negligence).
Appendix 1 - Drill hole collar and intersection information from +105 Level Block drill program at Prieska Copper-Zinc Project
Table 3: Collar table of 2022 PCZM +105 Level Crown Pillar resource drilling
Lo23 WGS84
Hole ID Azimuth Dip Length Hole Type Company Comment
Easting Northing Elevation
COC01 -68818.28 -3314095.36 1070.81 0.00 -90.00 73.41 Surface DD Repli
COC02 -68795.21 -3314074.15 1070.99 0.00 -90.00 72.80 Surface DD Repli
COC03 -68853.22 -3314060.15 1070.83 0.00 -90.00 71.86 Surface DD Repli
COC04 -68741.24 -3314162.28 1070.75 0.00 -90.00 63.70 Surface DD Repli
COC05 -68719.32 -3314141.02 1070.78 0.00 -90.00 107.86 Surface DD Repli
COC06 -68702.87 -3314251.15 1069.83 0.00 -90.00 55.50 Surface DD Repli
COC07 -68690.75 -3314233.74 1070.19 0.00 -90.00 70.92 Surface DD Repli
COC08 -68727.13 -3314218.22 1070.39 0.00 -90.00 61.30 Surface DD Repli
COC09 -68702.60 -3314194.88 1070.56 0.00 -90.00 89.50 Surface DD Repli
COC10 -68768.74 -3314119.22 1070.71 0.00 -90.00 72.90 Surface DD Repli
COC11 -68784.23 -3314143.78 1070.53 0.00 -90.00 45.67 Surface DD Repli
OCOD032 -68524.45 -3314513.33 1067.68 53.50 -35.70 58.86 Surface DD Orion No Assays, used for geological
modelling only
OCOD033 -68524.43 -3314513.40 1066.62 48.90 -22.31 186.14 Surface DD Orion
OCOD034 -68555.24 -3314485.35 1067.62 49.30 -22.00 82.88 Surface DD Orion No Assays, used for geological
modelling only
OCOD035 -68557.88 -3314484.86 1067.65 35.00 -17.00 184.68 Surface DD Orion
OCOD036 -68660.11 -3314387.84 1067.71 46.73 -24.23 149.25 Surface DD Orion
OCOD037 -68627.57 -3314423.73 1067.19 44.50 -23.20 157.69 Surface DD Orion
OCOD038 -68627.57 -3314423.73 1067.19 45.00 -19.10 141.21 Surface DD Orion
OCOD039 -68683.31 -3314217.11 1070.27 0.00 -90.00 84.27 Surface DD Orion No Assays, used for geological
modelling only
OCOD040 -68464.43 -3314547.58 1067.53 46.00 -15.56 149.41 Surface DD Orion
OCOD041 -68466.11 -3314549.27 1067.64 49.60 -23.70 119.79 Surface DD Orion No Assays, used for geological
modelling only
OCOD042 -68660.21 -3314387.01 1067.64 45.00 -16.12 111.78 Surface DD Orion
OCOD043 -68466.99 -3314550.24 1067.61 46.55 -29.63 202.33 Surface DD Orion
OCOD044 -68547.71 -3314477.66 1067.95 45.00 -10.30 94.58 Surface DD Orion
OCOD047 -68182.77 -3314677.71 1071.03 45.20 -28.70 177.84 Surface DD Orion
OCOD050 -68252.90 -3314634.73 1069.50 45.00 -30.00 122.01 Surface DD Orion
OCOD055 -68225.43 -3314661.09 1070.76 45.00 -30.00 185.00 Surface DD Orion No Assays, used for geological
modelling only
OCOD077 -68642.90 -3314255.63 1070.00 2.80 -88.90 90.93 Surface DD Orion No Assays, used for geological
modelling only
OCOD095 -68643.22 -3314287.96 1069.00 111.00 -60.00 111.90 Surface DD Orion No Assays, used for geological
modelling only
OCOD095A -68641.34 -3314288.40 1069.00 110.71 -60.61 30.40 Surface DD Orion No Assays, used for geological
modelling only
Lo23 WGS84
Hole ID Azimuth Dip Length Hole Type Company Comment
Easting Northing Elevation
OCOD097 -68516.78 -3314187.81 1067.00 179.22 -29.29 82.70 Surface DD Orion No Assays, used for geological
modelling only
OCOD097A -68516.70 -3314191.04 1067.00 179.91 -30.50 95.40 Surface DD Orion No Assays, used for geological
modelling only
OCOD098 -68258.01 -3314227.05 1068.87 222.43 -29.98 164.03 Surface DD Orion No Assays, used for geological
modelling only
OCOD099 -67994.49 -3314360.18 1069.51 223.63 -30.33 163.80 Surface DD Orion No Assays, used for geological
modelling only
OCOD106 -68667.34 -3314277.26 1069.46 273.43 -89.17 33.47 Surface DD Orion No Assays, used for geological
modelling only
OCOD106A -68665.51 -3314278.91 1069.44 77.46 -89.96 45.47 Surface DD Orion No Assays, used for geological
modelling only
OCOD108 -68665.51 -3314278.91 1069.44 224.13 -60.48 35.32 Surface DD Orion No Assays, used for geological
modelling only
OCOD138 -68680.07 -3314183.21 1070.11 264.91 -89.35 112.34 Surface DD Orion
OCOR012A -68869.19 -3314038.21 1070.77 225.00 -60.00 39.00 Surface RC Orion
OCOR013A -68839.45 -3314070.67 1070.97 225.00 -60.00 42.00 Surface RC Orion
OCOR014 -68808.98 -3314098.95 1070.83 225.00 -60.00 42.00 Surface RC Orion
OCOR015 -68748.62 -3314086.26 1070.82 0.00 -90.00 108.00 Surface RC Orion
OCOR016 -68694.12 -3314188.77 1070.60 154.60 -59.73 108.00 Surface RC Orion
OCOR017 -68675.70 -3314223.39 1070.22 145.00 -60.00 77.00 Surface RC Orion
OCOR018 -68687.06 -3314229.29 1070.20 0.00 -90.00 70.00 Surface RC Orion
OCOR019 -68682.01 -3314228.61 1070.15 0.00 -90.00 53.00 Surface RC Orion
OCOR020 -68735.58 -3314215.60 1070.31 225.00 -60.00 38.00 Surface RC Orion
OCOR021 -68756.68 -3314175.07 1070.51 225.00 -60.00 49.00 Surface RC Orion
OCOR022 -68714.45 -3314261.59 1069.70 225.00 -60.00 39.00 Surface RC Orion
OCOR023 -68692.07 -3314218.24 1070.35 0.00 -90.00 85.00 Surface RC Orion
OCOR024 -68678.43 -3314246.38 1068.03 0.00 -90.00 48.00 Surface RC Orion
OCOR025 -68654.38 -3314295.35 1069.34 0.00 -90.00 49.00 Surface RC Orion
OCOR026 -68659.05 -3314269.84 1069.50 330.00 -68.00 68.00 Surface RC Orion
OCOR027 -68640.98 -3314285.78 1069.29 111.00 -60.00 110.00 Surface RC Orion
OCOR028 -68644.41 -3314307.39 1069.20 225.00 -60.00 43.00 Surface RC Orion
OCOR029 -68669.86 -3314279.15 1069.46 225.00 -60.00 46.00 Surface RC Orion
OCOR030 -68745.18 -3314128.85 1070.83 0.00 -90.00 103.00 Surface RC Orion
OCOR031 -68783.93 -3314119.14 1070.66 225.00 -60.00 80.00 Surface RC Orion
OCOU071 -68087.90 -3314599.77 973.80 48.60 19.50 49.15 UG DD Orion No Assays, used for geological
modelling only
OCOU073 -68248.55 -3314550.07 974.27 55.50 25.00 62.33 UG DD Orion
OCOU075 -68255.66 -3314545.84 973.70 344.80 27.40 85.63 UG DD Orion
OCOU076 -68185.07 -3314600.28 972.94 39.70 27.20 68.15 UG DD Orion
OCOU078 -68055.87 -3314635.99 973.22 45.30 28.70 42.72 UG DD Orion No Assays, used for geological
modelling only
Lo23 WGS84
Hole ID Azimuth Dip Length Hole Type Company Comment
Easting Northing Elevation
OCOU079 -68329.89 -3314509.89 973.34 33.40 32.50 64.10 UG DD Orion No Assays, used for geological
modelling only
OCOU086 -68247.28 -3314551.54 974.36 55.00 25.00 69.92 UG DD Orion No Assays, used for geological
modelling only
OCOU088 -68329.59 -3314509.67 973.82 30.00 15.00 60.89 UG DD Orion No Assays, used for geological
modelling only
OCOU100 -68184.98 -3314599.43 973.25 21.74 40.00 75.26 UG DD Orion No Assays, used for geological
modelling only
OCOU102 -68371.48 -3314488.23 972.81 31.97 13.16 67.93 UG DD Orion No Assays, used for geological
modelling only
OCOU104 -68445.36 -3314444.07 974.95 355.01 14.15 82.56 UG DD Orion No Assays, used for geological
modelling only
OCOU109 -68437.99 -3314448.41 975.09 41.46 16.96 70.00 UG DD Orion No Assays, used for geological
modelling only
OCOU112 -68202.04 -3314619.10 972.70 37.78 34.31 90.52 UG DD Orion No Assays, used for geological
modelling only
V01 -68795.85 -3314074.21 1071.58 221.19 -55.00 60.96 Surface DD Anglovaal
V02 -68623.34 -3314231.79 1070.36 220.50 -60.00 121.92 Surface DD Anglovaal
V03 -68758.95 -3314020.57 1071.31 220.59 -60.00 121.92 Surface DD Anglovaal
V04 -68434.65 -3314306.16 1069.39 220.50 -60.00 134.30 Surface DD Anglovaal
V05 -68290.49 -3314453.39 1069.78 225.75 -60.00 108.51 Surface DD Anglovaal No Assays, used for geological
modelling only
V06A -67988.44 -3314571.63 1069.39 220.50 -60.00 134.70 Surface DD Anglovaal
V09 -68242.93 -3314413.77 1070.09 220.50 -60.00 126.50 Surface DD Anglovaal
V10 -68577.31 -3314184.24 1070.21 220.50 -60.00 139.60 Surface DD Anglovaal
V11 -68021.94 -3314600.89 1069.30 180.00 -90.00 199.34 Surface DD Anglovaal
V12 -68052.42 -3314631.68 1069.60 223.31 -60.00 302.97 Surface DD Anglovaal No Assays, used for geological
modelling only
V13 -68721.49 -3313971.80 1071.19 190.19 -60.00 182.88 Surface DD Anglovaal
V14 -68908.34 -3313902.92 1071.28 229.96 -60.00 178.31 Surface DD Anglovaal
OCOU141 -68523.15 -3314406.88 976.74 38.00 38.66 57.60 UG DD Orion
OCOU142 -68388.06 -3314476.31 974.17 37.00 33.71 71.51 UG DD Orion
OCOU143 -68523.27 -3314406.65 976.71 30.00 36.35 59.39 UG DD Orion
OCOU144 -68334.77 -3314505.10 972.76 35.00 9.69 67.74 UG DD Orion
OCOU145 -68522.87 -3314405.66 975.53 30.00 11.81 74.56 UG DD Orion
OCOU147 -68336.01 -3314506.50 974.00 20.00 42.28 46.89 UG DD Orion
OCOU148 -68482.39 -3314426.90 976.26 27.00 48.69 66.87 UG DD Orion
OCOU150 -68442.01 -3314446.95 973.63 21.00 10.78 54.50 UG DD Orion
OCOU151 -68262.72 -3314543.47 972.89 25.00 19.90 70.67 UG DD Orion
OCOU155 -68263.19 -3314544.65 973.70 25.00 44.97 63.02 UG DD Orion
OCOU156 -68442.75 -3314447.78 975.44 21.00 48.34 67.70 UG DD Orion
OCOU157 -68350.08 -3314498.24 973.99 32.00 31.51 52.10 UG DD Orion
Lo23 WGS84
Hole ID Azimuth Dip Length Hole Type Company Comment
Easting Northing Elevation
OCOU160 -68442.16 -3314447.19 974.85 14.00 33.00 62.09 UG DD Orion
OCOU163 -68418.39 -3314461.48 974.96 24.00 50.00 42.30 UG DD Orion
OCOU164 -68309.04 -3314520.31 974.07 25.00 35.35 75.00 UG DD Orion
OCOU166 -68417.84 -3314461.77 974.87 45.00 49.58 66.31 UG DD Orion
OCOU167 -68249.13 -3314550.51 973.81 55.00 50.00 39.56 UG DD Orion
OCOU168 -68545.95 -3314393.13 977.01 40.00 32.94 65.93 UG DD Orion
OCOU169 -68248.55 -3314550.07 974.00 58.00 56.71 42.88 UG DD Orion No Assays, used for geological
modelling only
Appendix 2: The following table is provided in accordance with the JORC Code (2012) requirements for the reporting of Mineral Resources for the
Prieska +105m Level Block
Section 1 Sampling Techniques and Data
(Criteria in this section apply to all succeeding sections.)
Criteria JORC Code explanation Commentary
Sampling techniques • Nature and quality of sampling (e.g. cut channels, random chips, or Drilling and sampling for the +105 Block has been undertaken during several
specific specialised industry standard measurement tools appropriate distinct periods since the discovery of mineralisation. These are pre-mine
to the minerals under investigation, such as down hole gamma sondes, exploration (1968-1971) surface diamond drill holes by Anglovaal Ltd (also
or handheld XRF instruments, etc.). These examples should not be known as the Anglovaal Group, “Anglovaal”), surface diamond drilling by
taken as limiting the broad meaning of sampling. Repli Investments No 27 (Pty) Ltd (Repli) in 2012, and surface and
• Include reference to measures taken to ensure sample representivity underground drilling and reverse circulation (RC) drilling by Orion (2017 to
and the appropriate calibration of any measurement tools or systems present).
used.
A total of 102 holes were drilled comprising 9,104m. Collar details for these
• Aspects of the determination of mineralisation that are Material to the holes are included as Table 1 in Appendix 1.
Public Report.
• In cases where ‘industry standard’ work has been done this would be • 12 surface diamond holes totalling 1,812m were drilled by Anglovaal.
relatively simple (e.g. ‘reverse circulation drilling was used to obtain 1 • 11 surface diamond holes totalling 785m were drilled by Repli in 2012.
m samples from which 3 kg was pulverised to produce a 30 g charge • 27 surface diamond holes totalling 3,173m were drilled by Orion in 2017.
for fire assay’). In other cases more explanation may be required, such • 20 RC holes totalling 1,297m were drilled by Orion in 2017.
as where there is coarse gold that has inherent sampling problems. • 13 underground diamond holes totalling 889m were drilled by Orion in
Unusual commodities or mineralisation types (e.g. submarine nodules) 2017.
may warrant disclosure of detailed information. • 19 underground diamond holes totalling 1,147m were drilled by Orion in
2022.
Orion acquired Repli in March 2017 and with the similar methodology
utilised in the drilling and sampling processes by both companies, Repli and
Orion commentary has in the most part been combined.
Anglovaal:
• For diamond drilling carried out by Anglovaal between 1968 and 1971,
there is limited information available on sampling techniques for core.
However, with exploration and resource management being carried out
under the supervision of Anglovaal, it is considered by the Competent
Person that there would be procedures in place to industry best practice
standard at that time. This is based on the Competent Persons
knowledge of exploration carried out by Anglovaal and discussions with
personnel employed by Anglovaal.
• The exploration and resource management were under the professional
supervision of Dr Danie Krige an internationally recognised expert of the
time who published peer reviewed papers based on the sampling data.
Criteria JORC Code explanation Commentary
The sampling was successful in defining a resource estimate which was
used as the basis of successful mine development and operation over a
20-year period.
• Drilling of the original surface exploration holes was carried out 200 –
250m line spacing.
• Surface drill exploration samples were all sent to Anglovaal Research
Laboratory at Rand Leases Mine and underground drill samples to the
mine laboratory for analyses.
• No records on the sampling methodology.
• Although no formal QA/QC samples were inserted at the time by the
geologists on the exploration site or the mine the Anglovaal Research
Laboratory developed their own standards, certified by other
commercial laboratories and those were used internally in the
laboratory. Duplicate samples were also inserted to check for
repeatability.
Repli and Orion:
• Samples submitted for analysis to Genalysis South Africa (Pty) Ltd
(Genalysis) (Repli) and ALS Chemex Pty Ltd (ALS) (Orion) are pulverised in
its entirety and split to obtain a 0.2g sample for digestion and analysis.
• Drilling was carried out on approximately 30m spaced lines along strike
and at approximately 50m intervals. There were however holes drilled in
between these lines. Underground holes, where possible, were spaced at
50m lines.
• Diamond core is cut at the core yard and half core taken as the sample.
• In friable ore where core splitting was not possible half of the broken
friable material was sampled using a spoon and scraper.
• Diamond core is sampled on 1m intervals where possible, sample lengths
are adjusted to ensure samples do not cross geological boundaries or
other features.
• RC samples were collected at 1m intervals via a cyclone and collected
in polyweave bags. Each sample was split via a 3 tier splitter, followed by
a single splitter to produce two samples of approximately 2.5kg each (an
“original” and a “duplicate”).
• Sampling is undertaken under the supervision of a qualified geologist and
intervals were selected on the basis of mineralogy, textures and
concentrations of specific minor minerals. A hand held Niton XRF
instrument is used as guide during sampling.
• Quality control samples were inserted under the direct supervision of a
geologist at pre-determined points within the sampling stream.
Criteria JORC Code explanation Commentary
Drilling techniques • Drill type (e.g. core, reverse circulation, open-hole hammer, rotary air Anglovaal:
blast, auger, Bangka, sonic, etc.) and details (e.g. core diameter, triple
or standard tube, depth of diamond tails, face-sampling bit or other • Records for core size are not available.
type, whether core is oriented and if so, by what method, etc.). • No records on core orientation
Repli and Orion:
• Diamond drilling from surface is with a NQ core size using a triple tube
core barrel to improve core recovery in soft formations.
• In the near surface weathered zone HQ core was drilled.
• Core is not orientated.
• RC holes have been drilled using a 140mm diameter RC hammer bit.
• Pre 2022 underground diamond drilling in the mineralised zone was
drilled using a TBW coring bit and a double tube core barrel and BX size
reverse flush in the country rock.
• 2022 underground diamond drilling was NQ size using a triple tube core
barrel to improve core recovery in soft formations.
Drill sample recovery • Method of recording and assessing core and chip sample recoveries Anglovaal:
and results assessed.
• All mineralised intersections were done with core drilling.
• Measures taken to maximise sample recovery and ensure
• Core recoveries are documented on the assay sheets. Core recoveries
representative nature of the samples.
were measured for each "run".
• Whether a relationship exists between sample recovery and grade
• In most holes recoveries were generally good through the mineralisation.
and whether sample bias may have occurred due to preferential
loss/gain of fine/coarse material. Repli and Orion:
• Core stick-ups reflecting the depth of the diamond drill hole are
recorded at the rig at the end of each core run.
• A block with the depth of the hole written on it is placed in the core box
at the end of each run.
• At the core yard, the length of core in the core box is measured for
each run. The measured length of core is divided by the stick-up
measured at the rig to determine the percentage core recovery.
Secondly, the measured length is subtracted from the length of the run
as recorded from the stick-up to determine the core lost.
• During surface drilling a triple tube core barrel is used to minimise the
core loss in soft formations.
• In underground holes a TBW bit was used to optimise core recovery
when drilling in the mineralised zone as opposed to reverse flush drilling
in the footwall rocks.
• Core loss was significant in some instances in the soft weathered
formations (oxides, supergene sulphide ore and clay zones).
• Analysis of data show that there is no relationship between core loss and
Criteria JORC Code explanation Commentary
grade.
Logging • Whether core and chip samples have been geologically and Anglovaal:
geotechnically logged to a level of detail to support appropriate
• All relevant intersections holes have been logged and all of this
Mineral Resource estimation, mining studies and metallurgical studies.
information is available.
• Whether logging is qualitative or quantitative in nature. Core (or
costean, channel, etc.) photography. Repli and Orion:
• The total length and percentage of the relevant intersections logged.
• RC drill chips were logged on 1m intervals using visual inspection of
washed drill chips.
• Core of the entire hole length was geologically logged and recorded
on standardised log sheets by qualified geologists.
• All intersections were logged.
• Qualitative logging of colour, grainsize, weathering, structural fabric,
lithology, alteration type and mineralogy was carried out.
• After logging the information was entered into digital templates at the
project office.
• The Orion drilled core was all (entire drill hole) photographed and saved
in a dedicated folder.
Sub-sampling • If core, whether cut or sawn and whether quarter, half or all core Anglovaal:
techniques and taken.
• Details of sub-sampling techniques not available
sample preparation • If non-core, whether riffled, tube sampled, rotary split, etc. and
• No QAQC samples submitted with the exploration samples
whether sampled wet or dry.
• For all sample types, the nature, quality and appropriateness of the Repli and Orion:
sample preparation technique.
• Quality control procedures adopted for all sub-sampling stages to • RC chip samples were split via a 3-tier splitter, followed by a single splitter
maximise representivity of samples. to produce two samples of approximately 2.5kg each (an “original” and
• Measures taken to ensure that the sampling is representative of the in- a “duplicate”).
situ material collected, including for instance results for field • When wet, the chip samples were allowed to dry before it was split and
duplicate/second-half sampling. sampled.
• Whether sample sizes are appropriate to the grain size of the material • With core samples, the entire sample length was cut, and one half
being sampled. sampled.
• In friable ore where core splitting was not possible half of the broken
friable material was sampled using a spoon and scraper.
• Core samples were dry.
• Three laboratories were used: the drilling campaign by Repli used
Genalysis and the two campaigns by Orion used ALS. Both laboratories
have SANAS accreditation. However, Genalysis only have accreditation
for Au and Pb. SGS Laboratory was used as the referee laboratory.
• Samples submitted to the primary laboratories were dried and crushed
to 70% < 2mm and then pulverised to 85% < 75 microns.
• Quality control samples were inserted (> 8% insertion rate) under the
direct supervision of a geologist at pre-determined points within the
sampling stream. Blanks were inserted at the beginning and end of
each batch as well as within the mineralised zone of each drill hole.
CRM was inserted to correspond more or less with low, medium or high
grade mineralised zones.
• ALS has their own internal QA/QC protocols which include CRM’s (5%),
blanks (2.5%) and duplicates (2.5%).
• Due to the poor quality of the core and difficulty to cut half core into
quarter core only a few field duplicates could be taken.
• Pulp duplicates for repeatability checks were submitted to SGS as
referee laboratory.
Quality of assay data • The nature, quality and appropriateness of the assaying and Anglovaal:
and laboratory tests laboratory procedures used and whether the technique is considered
partial or total. • Surface drill exploration samples were all sent to Anglovaal Research
Laboratory at Rand Leases Mine.
• For geophysical tools, spectrometers, handheld XRF instruments, etc.,
the parameters used in determining the analysis including instrument • Atomic Adsorption method was used with a Nitric-bromide digest.
make and model, reading times, calibrations factors applied and their
derivation, etc. • Although no formal QA/QC samples were inserted with the drill samples
of the exploration holes the Anglovaal Research Laboratory developed
their own standards, certified by other commercial laboratories and
those were used internally in the laboratory. Duplicate samples were also
inserted to check for repeatability.
• Nature of quality control procedures adopted (e.g. standards, blanks,
duplicates, external laboratory checks) and whether acceptable
levels of accuracy (i.e. lack of bias) and precision have been
established.
Repli and Orion:
• Three laboratories were used to analyse samples. Repli used Genalysis
and Orion used ALS with SGS Laboratory used as the referee laboratory.
• Analyses were done using acid digestion and the inductively coupled
plasma and optical emission spectroscopy (“ICP-OES”) methodology.
Acid digestions were as follows:
• Initially ALS used a three-acid digest, but changed to an aqua-regia
digest in November 2017.
• Genalysis used a four-acid digest.
• SGS an aqua-regia digest
• Quality control samples were inserted, under the direct supervision of a
geologist, at pre-determined points within the sampling stream. Sample
results of the duplicates and CRMs were examined on a regular basis by
the responsible geologist and any discrepancy taken up with the
laboratories.
• CRM samples show excellent accuracy and precision and duplicate
samples show acceptable precision with no obvious bias. Blank samples
indicate no contamination, within the pre-determined thresholds, during
the sample preparation process.
• External laboratory checks between ALS and SGS were done by
submission of duplicate samples. These show excellent accuracy and
precision, except for the Au as can be expected with the very low
levels.
Verification of • The verification of significant intersections by either independent or Anglovaal:
sampling and alternative company personnel.
• No records available
assaying • The use of twinned holes.
• Documentation of primary data, data entry procedures, data Repli and Orion:
verification, data storage (physical and electronic) protocols.
• Discuss any adjustment to assay data. • The drilling and sampling of each drilling campaign was supervised by
experienced geologists.
• Core recovery, density data, sampling data and geological logs are
documented in the core yard onto standard paper templates provided
by the company.
• Data entry from the primary hard copies is done on excel spreadsheets
by the geologists logging the core. The data is then imported in to an
Access database by the geologist responsible for the database.
Validation of the data is done during importing into the Access
database by running queries, and when the resource geologist imports
the data into to the modelling software.
• No twinning of holes has been done.
• No adjustments have been made to the assay data.
Location of data points • Accuracy and quality of surveys used to locate drill holes (collar and Anglovaal:
down-hole surveys), trenches, mine workings and other locations used
• All surface collars were surveyed by qualified surveyors using a
in Mineral Resource estimation.
theodolite.
• Specification of the grid system used.
• The historic mine survey data is in the old national Lo 23 Clarke 1880
• Quality and adequacy of topographic control.
coordinate system.
• Downhole surveys were carried out for the holes. Methodology of the
downhole surveys is not recorded on the available hardcopy information
but plans and sections are meticulously plotted and signed off by a
certified surveyor.
• Both Eastman and Sperry Sun instruments were used in the downhole
surveys.
• All hole positions have been converted to Lo23 WGS84 coordinates.
Repli and Orion:
• Drill hole collar positions were laid out using a handheld GPS.
• After completion of the drilling all collars were surveyed by a qualified
surveyor using a Trimble R8 differential GPS.
• Downhole surveys of Orion diamond drill holes were completed using a
Criteria JORC Code explanation Commentary
North-Seeking Gyro instrument. Repli diamond drill holes were surveyed
downhole using a Reflex EZ Track multi-shot survey instrument.
• No downhole surveys were done in the RC holes.
• All survey data is in the WGS84 ellipsoid in the WG23 Zone with the
Hartebeeshoek 1994 Datum. The coordinates are also supplied in Clarke
1880 and in UTM WGS84 Zone 34 (Southern Hemisphere).
Data spacing and • Data spacing for reporting of Exploration Results. Anglovaal:
distribution • Whether the data spacing and distribution is sufficient to establish the
degree of geological and grade continuity appropriate for the Mineral • Holes were drilled on 200 - 250 m spacing.
Resource and Ore Reserve estimation procedure(s) and classifications Repli and Orion:
applied.
• Whether sample compositing has been applied. • Drilling was carried out on approximately 30m spaced lines along strike
and at approximately 50m intervals. There were, however, a few holes
drilled in between these lines. Underground holes, where possible, were
spaced at 50m lines.
• Variography studies were carried out on the historic data set to
determine the drill spacing for Mineral Resource estimates.
• No sample compositing has been applied before assaying.
Orientation of data in • Whether the orientation of sampling achieves unbiased sampling of • Where access allows, drilling is oriented perpendicular, or at a maximum
relation to geological possible structures and the extent to which this is known, considering achievable angle to, the attitude of the mineralisation.
structure the deposit type. • Due to the presence of sinkholes, access was restricted over half of the
• If the relationship between the drilling orientation and the orientation strike length and drilling had to be executed from the footwall side of
of key mineralised structures is considered to have introduced a the mineralised horizon, which resulted in sub-optimal angles of
sampling bias, this should be assessed and reported if material. intersection. The orientations of these holes are, however not considered
of significance to the resource estimation by the Competent Person.
• No sampling bias is anticipated as a result of hole orientations.
Sample security • The measures taken to ensure sample security. Anglovaal:
• No details of sample security available. However, during the mining
operations the site was fenced and gated with security personnel
employed as part of the staff.
Repli and Orion:
• Access to drill sites are limited to responsible persons, close supervision of
the unloading of the core tube and transportation of core to the core
yards (Repli’s in Kimberley and Orion’s on site). Both core yards are
enclosed by a security fence, the access gate of which were locked at
all times when personnel were not on the premises.
• Sample shipments were controlled by the geologists and / or
technicians. In the case of the Repli samples geologists and technicians
Criteria JORC Code explanation Commentary
were responsible for the transportation of samples to the Genalysis
laboratory in Johannesburg. Orion samples were sent with a courier
service to the ALS laboratory in Johannesburg. Sample shipments were
accompanied with appropriate sign off documentation to ensure all
samples were received in good order.
• The chain of custody was managed by the individual Companies.
Samples were stored on site in a secure locked building and then
freighted directly to the laboratory.
Audits or reviews • The results of any audits or reviews of sampling techniques and data. Anglovaal:
• No records available.
Repli and Orion:
• SRK reviewed a previous Mineral Resource statement document in
November 2017.
• Their main concern was the water displacement method with lacquer
spray used to determine the relative density of the oxide and supergene
sulphide mineralisation.
• A total of 33% of the samples lying within the wireframe used for the
estimation of the supergene sulphide mineralisation were re-done for
relative density using the wax relative density method. These results show
excellent precision and no obvious bias when comparing with the
original relative densities.
• Core from the +105 Block holes and storage facilities has been visually
examined by the Competent Person. Discussions have taken place with
Repli on the conduct of the drilling programme, sampling techniques
and handling of data and the Competent Person is satisfied that work
was carried out to JORC 2012 standards.
Section 2 Reporting of Exploration Results
(Criteria listed in the preceding section also apply to this section.)
Criteria JORC Code explanation Commentary
Mineral tenement and • Type, reference name/number, location and ownership including • The Mining Right is held by Prieska Copper Zinc Mine (Pty) Ltd (PCZM)
land tenure status agreements or material issues with third parties such as joint ventures, (formerly Repli Trading No. 27 (Pty) Ltd), which is a wholly owned
partnerships, overriding royalties, native title interests, historical sites, subsidiary of Orion. Orion effectively holds a 70% interest in the project.
wilderness or national park and environmental settings. • The Mining Right covers the complete known strike of the +105 Level
• The security of the tenure held at the time of reporting along with any Resource.
known impediments to obtaining a licence to operate in the area. • +105 Level Resource is located on Portion 26 of the farm Vogelstruis-Bult
104.
Exploration done by • Acknowledgment and appraisal of exploration by other parties. • The Anglovaal exploration resulted in the delineation and development
other parties of a large mine.
• Drilling in 2012 of the north-western section of the +105 Block was carried
out by Repli (Orion acquired Repli in March 2017).
Geology • Deposit type, geological setting and style of mineralisation. • The Copperton deposit is a Volcanogenic Massive Sulphide (VMS)
deposit which is situated in the southernmost exposures of the north-
northwest trending Kakamas Terrain, which forms part of the Mid-
Proterozoic Namaqualand Metamorphic Complex.
• The deposit is hosted by the Copperton Formation of the Areachap
Group. The Areachap Group, also hosts several other but smaller VMS
deposits such as the Areachap, Boks Puts, Kantien Pan, Kielder, and
Annex Vogelstruisbult deposits.
• The structural sequence at the mine consists of a footwall Smouspan
Gneiss Member, Prieska Copper Mines Assemblage (PCMA), which hosts
the sulphide mineralisation, and the hangingwall Vogelstruisbult Gneiss
Member.
• The historically mined section of the deposit is confined to a tabular,
stratabound horizon in the northern limb of a refolded recumbent
synform, the axis of which plunges at approximately 5° to the south-east.
• The mineralised zone outcrop has a strike of 2.400m, is oxidised and / or
affected by leached and supergene enrichment to a depth of
approximately 100m and crops out as a well-developed gossan. It has a
dip of between 55° and 80° to the northeast at surface and a strike of
130° to the north. Current drilling indicates that the Deep Sulphides has a
strike length of at least 2860m at depth.
• The thickness of the mineralised zone exceeds 30m in places but
averages between 7m and 9m. The mineralised zone persists to a depth
of 1,100m (as deep as 1,228m in one section) after which it is upturned
due to the folding.
• The Deep Sulphide Mineral Resource area located below the historical
mined area, comprises the steep down dip continuity ("steep limb and
hinge zone”) and from where it upturns to its subsequent synformal
structure ("trough zone").
• The morphology of the mineralised horizon in the eastern limb is well
mapped out by drilling and historic mining while the western limb up dip
extent is poorly tested and mapped.
• The +105 Block area comprises the oxide/supergene sulphide/ mixed
zone (and a zone of remnant primary sulphides) situated from above
the upper limit of mining at approximately 100m depth below surface,
up to surface. This zone of oxide and supergene sulphide mineralisation
has a strike length of approximately 1,000m.
Drill hole Information • A summary of all information material to the understanding of the Anglovaal:
exploration results including a tabulation of the following information • A summary of the Anglovaal drill hole collar is included in Table 3.
for all Material drill holes:
o easting and northing of the drill hole collar Repli and Orion:
o elevation or RL (Reduced Level – elevation above sea level in
metres) of the drill hole collar • All drilling information is available and has been compiled digitally.
o dip and azimuth of the hole • A summary of the drill hole collar information related to the current
o down hole length and interception depth +105 Level Mineral Resource reporting is given in Table 3.
o hole length.
• If the exclusion of this information is justified on the basis that the
information is not Material and this exclusion does not detract from the
understanding of the report, the Competent Person should clearly
explain why this is the case.
Data aggregation • In reporting Exploration Results, weighting averaging techniques, Anglovaal:
methods maximum and/or minimum grade truncations (e.g. cutting of high • Individual intersections were weighted by sample width.
grades) and cut-off grades are usually Material and should be stated.
• No truncations have been applied.
• Where aggregate intercepts incorporate short lengths of high grade • All grade and density information are incorporated in the Orion
results and longer lengths of low grade results, the procedure used for database.
such aggregation should be stated and some typical examples of
such aggregations should be shown in detail. Repli and Orion:
• The assumptions used for any reporting of metal equivalent values
should be clearly stated. • All drilling information is available and has been compiled digitally.
• All intersections > 1m and >0.3% copper or > 0.6% zinc were quoted in
public reporting.
• No truncations have been applied.
• No metal equivalent values were considered.
Relationship • These relationships are particularly important in the reporting of • All intersection widths quoted are down hole widths.
between Exploration Results. • Most holes intersected the mineralisation perpendicular or at high angle
• If the geometry of the mineralisation with respect to the drill hole angle to the attitude of the mineralisation.
mineralisation
Criteria JORC Code explanation Commentary
widths and is known, its nature should be reported. • The geometry of the mineralisation is complex and true widths can be
intercept lengths • If it is not known and only the down hole lengths are reported, there obtained from the three-dimensional wireframe created of the
should be a clear statement to this effect (e.g. ‘down hole length, true mineralisation.
width not known’).
Diagrams • Appropriate maps and sections (with scales) and tabulations of • Appropriate diagrams (cross section and long section) are shown in
intercepts should be included for any significant discovery being Figures 1 and 2.
reported. These should include, but not be limited to a plan view of drill
hole collar locations and appropriate sectional views.
Balanced reporting • Where comprehensive reporting of all Exploration Results is not • All drilling information is available and has been compiled digitally.
practicable, representative reporting of both low and high grades
and/or widths should be practiced to avoid misleading reporting of
Exploration Results.
Other substantive • Other exploration data, if meaningful and material, should be reported • Hardcopy plans are available for a range of other exploration data. This
exploration data including (but not limited to): geological observations; geophysical includes mine survey plans, geological maps, airborne magnetic, ground
survey results; geochemical survey results; bulk samples – size and magnetic, electromagnetic, gravity and induced polarisation
method of treatment; metallurgical test results; bulk density, information. All available exploration data has been viewed by the
groundwater, geotechnical and rock characteristics; potential Competent Person.
deleterious or contaminating substances. • The Prieska Mine operated from 1972 to 1991 and is reported to have
milled a total of 45.68 Mt of ore at a grade of 1.11% copper and 2.62%
zinc, recovering 0.43 Mt of copper and 1.01 Mt of zinc. Detailed
production and metallurgical results are available for the life of the mine.
• In addition, 1.76 Mt of pyrite concentrates and 8,403 t of lead
concentrates as well as amounts of silver and gold were recovered.
• Copper and zinc recoveries averaged 84.9% and 84.3% respectively
during the life of the mine.
• Comprehensive geotechnical work was completed as part of a
Bankable Feasibility Study (BFS) and the data is available.
• Metallurgical test work as part of a BFS update is in progress. All data to
date is available.
Further work 1. The nature and scale of planned further work (e.g. tests for lateral • No additional drilling is planned.
extensions or depth extensions or large-scale step-out drilling). • Metallurgical test work is underway as part of a BFS update.
2. Diagrams clearly highlighting the areas of possible extensions, • Once project is approved grade control drilling will be executed and
including the main geological interpretations and future drilling areas, areas of uncertainty will be covered by this drilling.
provided this information is not commercially sensitive.
Section 3 Estimation and Reporting of Mineral Resources
(Criteria listed in section 1, and where relevant in section 2, also apply to this section.)
Criteria JORC Code explanation Commentary
Database integrity • Measures taken to ensure that data has not been corrupted by, for • Drill hole and sample data are stored by Orion in a robust GeobankTM
example, transcription or keying errors, between its initial collection database.
and its use for Mineral Resource estimation purposes. • Validation includes the following:
• Data validation procedures used. o Ensuring that all drill holes have appropriate XYZ coordinates.
o Comparing the maximum depth of the hole against the final depth
indicated in the collar file.
o Comparing the final depth in the survey file against final depth in
the collar file.
o Comparing the final depths of all geology, assay, core recovery
against the final depth in the collar file.
o Checking for duplicate drill holes.
o Checking that each depth interval has a main lithology.
o Checking that all fields that were set up as mandatory fields contain
entries.
o The core recoveries were checked for unrealistic percentages.
o Density results are checked for unrealistic values.
• Additional validation was undertaken when the drill hole data was
imported into the Geovia GEMSTM modelling software. The data was
checked for duplicates, gaps, overlaps, impossible intervals in down-hole
sequence for assay, collar coordinates, geology data and survey data.
The drill holes were also visually checked in plan and section in GEMS.
• Additional validation was also undertaken when the data was imported
into DatamineTM and then when the de-surveyed data was imported to
IsatisTM for the EDA and the estimation.
Site visits • Comment on any site visits undertaken by the Competent Person • Z Star Mineral Resource Consultants (Pty) Ltd were requested by Orion
and the outcome of those visits. Services South Africa (Pty) Ltd to update an Mineral Resource estimate
• If no site visits have been undertaken indicate why this is the case. and classification for the +105m Level deposit. They visited the site in
October 2017 and February 2018. The visits included a review of the
drilling and sampling operations, discussion on the geology and
associated mineralisation, review of the planned drill holes and
examination of the assay data and a high level spatial analysis.
Geological • Confidence in (or conversely, the uncertainty of) the geological • The +105m Level resource model comprises six defined geological zones.
interpretation interpretation of the mineral deposit. These are:
• Nature of the data used and of any assumptions made. o Haematite-goethite-quartz oxide zone (gossan) from surface to
• The effect, if any, of alternative interpretations on Mineral Resource approximately 33m;
estimation. The use of geology in guiding and controlling Mineral o Clay (kaolinite)/leach zone developed in places below 33m;
Resource estimation. o Chalcocite dominant supergene sulphide zone between
Criteria JORC Code explanation Commentary
• The factors affecting continuity both of grade and geology. approximately 42m and 70m; and
o Mixed supergene sulphide zone between approximately 70m and
90m below surface. This has a relatively sharp contact with the fresh
underlying massive sulphides.
o Hypogene zone is the fresh underlying massive sulphides.
o A separate zone of elevated Cu and Zn values in the oxides (where
there is adequate drilling information) in the hangingwall (HW) to
the main +105m Level crown pillar is present in the northwest of the
deposit or approximately 300m strike where the zone converges
with the main zone towards the southeast.
• All of the above six zones apart from the second (clay/leach zone), are
considered as being suitable for inclusion as part of the Mineral
Resource. The Oxide and HW Oxide are referred to as the Oxide Zone.
The Supergene Sulphide, Mixed and Hypogene zones are collectively
referred to as the Supergene Sulphide & Hypogene Zone.
• The boundaries of the mineralisation are relatively sharp irrespective of
the geology. A wireframe of the combined +105 Level crown pillar
mineralisation was created by interpretation of the Cu and Zn values
along 47 sections across the deposit. The wireframe was constructed
utilising Cu values greater than or equal to 0.3% and Zn values greater
than or equal to 0.6%. Where possible both values were utilised during
modelling, but greater emphasis was placed on the copper values as
the zinc was leached out towards surface. In places, this resulted in the
inclusion of mineralised areas based only on high Cu values.
• In the NW part of the deposit, mineralisation occurs in two lenses, the
main crown pillar mineralisation and a HW zone. It is unclear whether this
HW zone is stacked mineralisation formed during deposition or a
structural duplication due to thrusting or isoclinal folding and will be
investigated with detailed grade control drilling in the operational phase.
The upper lens does not seem to have depth extent and is part of the
oxide zone. It merges with the main crown pillar mineralisation towards
the southeast.
• Surfaces representing the bottoms of the Oxide Zone, the Leach Zone
and the Supergene Sulphide Zone were interpreted and modelled from
drillhole data. A bottom of overburden was created 3m below the
topographic surface. A surface was created to represent the upper limit
of underground stoping.
• Geological data and conclusions reached are based on observations in
drill core.
• The Oxide and Supergene Sulphide & Hypogene zones are treated
separately in the resource estimation.
Criteria JORC Code explanation Commentary
Dimensions • The extent and variability of the Mineral Resource expressed as • The strike length of the +105 Level Crown Pillar mineralisation is
length (along strike or otherwise), plan width, and depth below approximately 1km from the northwest to where the zone intersects the
surface to the upper and lower limits of the Mineral Resource. sinkholes in the southeast. The depths below surface to the upper limits
are 3m and to the lower limits from 100m to 120m below surface.
• Thickness of the mineralised zone varies from 1.5m to 23m.
Estimation and • The nature and appropriateness of the estimation technique(s) • Density weighting is standard practice for VMS deposits. However, in the
modelling techniques applied and key assumptions, including treatment of extreme grade Oxide and Supergene Sulphide & Hypogene zones the density
values, domaining, interpolation parameters, and maximum measurements do not correlate well with the assay values and density
distance of extrapolation from data points. If a computer assisted weighting was therefore not included. The poor correlation is probably
estimation method was chosen include a description of computer due to the friable nature of the core.
software and parameters used. • The distribution of composites for each of the variables (Cu, Zn, and
• The availability of check estimates, previous estimates and/or mine density) were assessed and a decision was taken to utilise the Parker
production records and whether the Mineral Resource estimate methodology for capping outliers. The process involved capping the
takes appropriate account of such data. relevant outliers for each variable to a chosen threshold.
• The assumptions made regarding recovery of by-products. • Five Cu and two Zn assays were capped in the Oxide Zone. Capping
• Estimation of deleterious elements or other non-grade variables of was applied to seven Cu assays and four Zn assays in the Supergene
economic significance (e.g. sulphur for acid mine drainage Sulphide & Hypogene Zone.
characterisation). • DatamineTM was utilised to create a block model and measure individual
• In the case of block model interpolation, the block size in relation to block volumes within each zone and these data were imported into
the average sample spacing and the search employed. IsatisTM for further analysis.
• Any assumptions behind modelling of selective mining units. • The Oxide and Supergene Sulphide & Hypogene zones were analysed
• Any assumptions about correlation between variables. independently to ensure that the plane for estimation had an optimal
• Description of how the geological interpretation was used to control orientation.
the resource estimates. • Variograms for all variables were created from the laboratory assay
• Discussion of basis for using or not using grade cutting or capping. capped composites only and modelled in two directions, downhole
• The process of validation, the checking process used, the (along the drill hole) and omni-directionally on the plane of the
comparison of model data to drill hole data, and use of mineralisation. Assessment of the variogram models was preferentially
reconciliation data if available. focused on the Cu and Zn spatial structure.
• No mining production took place above the 105 level of the mine.
• No assumptions have been made regarding the recovery of by-
products.
• No deleterious elements or non-grade variables were estimated.
• A block model was created to allow estimation into 40m x 40m x 5m
blocks with sub-cells of 1m x 1m x 1m.
• Ordinary kriging (OK) was undertaken on all variables on a 40m x 40m x
5m block scale, utilising the capped composite input datasets and the
modelled variograms. Estimation runs on two different neighbourhoods
were utilised for all variables and the first estimation run in each case has
smaller searches (equivalent to the variogram ranges), particularly in the
Z direction. This ensures that the variography and therefore the nature of
Criteria JORC Code explanation Commentary
the mineralisation is honoured and ensures that negative weights are
minimised. The neighbourhood of the second kriging run was expanded
to allow population of most of the remaining blocks. The 2nd pass kriging
run failed to populate all the blocks in the Oxide and Supergene
Sulphide & Hypogene Zones, particularly in areas where the peripheral
dip of the deposit was different to the best fit plane. A decision was
taken to utilise the “grid filling” option in IsatisTM using a moving average
interpolator.
• For the Oxide domain, neighbourhood analysis resulted in an optimum
search neighbourhood of 100m x 4m for local block estimation by OK,
corresponding to the variogram range. The second and third pass
estimates were calculated from the pass 1 OK estimates using a moving
average technique with the search radii increased to 200m / 7m and
400m / 20m respectively. 51% of blocks were estimated by the first pass.
• For the Supergene Sulphide & Hypogene domain, neighbourhood
analysis resulted in an optimum search neighbourhood of 100m x 7.2m
for local block estimation by OK, corresponding to the variogram range.
The second and third pass estimates were calculated from the pass 1 OK
estimates using a moving average technique with the search radii
increased to 200m / 7m and 400m / 20m respectively. 80% of blocks were
estimated by the first pass.
• The kriging performance parameters, e.g. slope of regression, together
with an assessment of the areas of blocks that were populated by 1st
pass kriging, were utilised to make a distinction between the Indicated
and Inferred classifications.
• No assumptions were made regarding selective mining methods.
• The Oxide and Supergene Sulphide & Hypogene zones are reported
independently in the Mineral Resource statement.
Moisture • Whether the tonnages are estimated on a dry basis or with natural • No moisture content was calculated, and the core was naturally dried
moisture, and the method of determination of the moisture content. when logged and sampled. The estimated tonnages are therefore
based on a natural basis.
Cut-off parameters • The basis of the adopted cut-off grade(s) or quality parameters • The Mineral Resource is reported above a cut-off of 0.3% Cu which
applied. corresponds with the wireframe modelling.
• The cut-off is based on historical data from the Prieska Mine and a
dataset of parameters from similar operations in the region.
Criteria JORC Code explanation Commentary
Mining factors or • Assumptions made regarding possible mining methods, minimum • Options of using open cast mining methods with 10m benches and
assumptions mining dimensions and internal (or, if applicable, external) mining underground mining methods are currently under consideration.
dilution. It is always necessary as part of the process of determining • The major risk is mining between sinkholes and above the partly
reasonable prospects for eventual economic extraction to consider collapsed crown pillar of the underground mined-out stopes.
potential mining methods, but the assumptions made regarding • Whittle pit optimisation study and detail pit design, as part of a Bankable
mining methods and parameters when estimating Mineral Feasibility Study has been completed. Underground mine design is in
Resources may not always be rigorous. Where this is the case, this progress.
should be reported with an explanation of the basis of the mining
assumptions made.
Metallurgical factors • The basis for assumptions or predictions regarding metallurgical • Metallurgical test work indicated that a separate copper and zinc
or assumptions amenability. It is always necessary as part of the process of concentrate of the supergene sulphide mineralisation is achievable.
determining reasonable prospects for eventual economic • Ore extracted from the +105 mineralised zone was previously treated
extraction to consider potential metallurgical methods, but the using froth flotation metallurgical process by Prieska Copper Mine. Mixed
assumptions regarding metallurgical treatment processes and oxide, supergene and hypogene sulphide ore was successfully treated
parameters made when reporting Mineral Resources may not by froth flotation to produce separate copper and zinc concentrates
always be rigorous. Where this is the case, this should be reported during the 1980’s².
with an explanation of the basis of the metallurgical assumptions • Test work of the oxide mineralisation however was limited but
made. unsuccessful. The oxide mineralisation has a reasonable prospect for
eventual economic extraction as it occurs close to the surface and
treatment of this type of ore by means of leaching is well known in the
industry.
Environmental factors • Assumptions made regarding possible waste and process residue • The +105 Level Resource is on the environmental footprint of the historical
or assumptions disposal options. It is always necessary as part of the process of Prieska Copper Mine site. Environmental impact assessment studies form
determining reasonable prospects for eventual economic part of the on-going BFS.
extraction to consider the potential environmental impacts of the
mining and processing operation. While at this stage the
determination of potential environmental impacts, particularly for a
greenfields project, may not always be well advanced, the status of
early consideration of these potential environmental impacts should
be reported. Where these aspects have not been considered this
should be reported with an explanation of the environmental
assumptions made.
Bulk density • Whether assumed or determined. If assumed, the basis for the • Due to the poor core recoveries, the density data in the Oxide Zone is
assumptions. If determined, the method used, whether wet or dry, sparse with only 48 samples available. There are 203 density
the frequency of the measurements, the nature, size and measurements in the Supergene Sulphide & Hypogene Zone.
representativeness of the samples. • Bulk densities were determined using the water displacement method. A
• The bulk density for bulk material must have been measured by representative sample of full core at 15cm length was collected per
methods that adequately account for void spaces (vugs, porosity, metre length, taking cognisance of the change in lithology.
etc), moisture and differences between rock and alteration zones • A total of 33% of the samples lying within the wireframe used for the
Criteria JORC Code explanation Commentary
within the deposit. estimation of the Supergene Sulphide mineralisation were re-done for
• Discuss assumptions for bulk density estimates used in the evaluation relative density using the wax relative density method. These results show
process of the different materials. excellent precision and no obvious bias when comparing with the
original relative densities.
• No moisture content was determined.
• Core is mostly weathered in the Oxide Zone with obvious core loss. The
representative samples selected for density measurement were sprayed
with a clear lacquer spray and allowed to dry prior to being weighed.
• The bulk density in the Oxide Zone was estimated using OK.
• The density in the Supergene Sulphide & Hypogene Zone was estimated
using OK.
Classification • The basis for the classification of the Mineral Resources into varying • The geology of the zones making up the +105m Level Mineral Resource is
confidence categories. relatively uncomplicated, and the key issues relate to the delineation of
• Whether appropriate account has been taken of all relevant the domain boundaries (not geology). The assay data used for
factors, i.e. relative confidence in tonnage/grade estimations, estimation is reliable and has been acquired with good governance
reliability of input data, confidence in continuity of geology and associated with all processes. The variables were estimated using
metal values, quality, quantity and distribution of the data. independent variogram models and OK.
• Whether the result appropriately reflects the Competent Person(s)’ • Oxide Zone: Inferred and Indicated Mineral Resource - the geological
view of the deposit. model is defined to a reasonable level and there is sufficiently accurate
data to produce local block estimates using OK, albeit there is a limited
number of samples in some areas, especially in the southeast where
surface drilling access was restricted by the presence of sinkholes. There
is a high level of uncertainty associated with the zonal estimation of
density due to a low number of samples (and a possible bias in the
methodology) as well as possible inaccuracies associated with core loss.
Two collapse zones (related to collapse in the sinkhole) have been
interpreted up-dip based on drilling information from the Supergene
Sulphide zone.
• Supergene Sulphide & Hypogene Zone: Inferred and Indicated Mineral
Resources - the geological model is defined to a reasonable level and
there is sufficiently accurate data coverage to produce local block
estimates using OK. In parts of the Supergene Sulphide Zone there are
sufficient data for reasonably accurate local block estimates of grade
(~80% of volume populated by 1st Pass kriging). The low number of
density samples is a concern but local block estimation with reasonable
accuracy was possible. The kriging performance parameters, e.g. slope
of regression, together with an assessment of the areas of blocks that
were populated by 1st pass kriging, were utilised to make a distinction
between the Indicated and Inferred levels of confidence.
• The results conform to the view of the Competent Person.
Criteria JORC Code explanation Commentary
Audits or reviews • The results of any audits or reviews of Mineral Resource estimates. • To date the Mineral Resource estimate has only been reviewed internally
by Orion.
Discussion of relative • Where appropriate a statement of the relative accuracy and • Final estimates for all variables in both zones were validated by
accuracy/confidence confidence level in the Mineral Resource estimate using an comparing the mean composite grades to the mean estimate grades.
approach or procedure deemed appropriate by the Competent The data for Cu and Zn with the 1st Pass and final estimates are within 5%
Person. For example, the application of statistical or geostatistical of the composites mean for the Supergene Sulphide & Hypogene Zone
procedures to quantify the relative accuracy of the resource within and the Oxide Zone.
stated confidence limits, or, if such an approach is not deemed • Composite and estimated final grade and density distributions were
appropriate, a qualitative discussion of the factors that could affect compared to ensure that the block estimates represent the original data
the relative accuracy and confidence of the estimate. distribution. These were found to be reasonably compatible.
• The statement should specify whether it relates to global or local • Swathe Trend plots were created in the Y, X and Z directions and all the
estimates, and, if local, state the relevant tonnages, which should estimates followed the trend of the composite data.
be relevant to technical and economic evaluation. Documentation • All estimates were studied graphically and compared to the composite
should include assumptions made and the procedures used. data in three-dimensional space and they compared reasonably well,
• These statements of relative accuracy and confidence of the given the high variability of the sample data.
estimate should be compared with production data, where • No production data is available.
available.
Date: 25-07-2023 09:01:00
Produced by the JSE SENS Department. The SENS service is an information dissemination service administered by the JSE Limited ('JSE').
The JSE does not, whether expressly, tacitly or implicitly, represent, warrant or in any way guarantee the truth, accuracy or completeness of
the information published on SENS. The JSE, their officers, employees and agents accept no liability for (or in respect of) any direct,
indirect, incidental or consequential loss or damage of any kind or nature, howsoever arising, from the use of SENS or the use of, or reliance on,
information disseminated through SENS.
Sharenet Sites 
