Tharisa : Karo Mineral Reserve and Mineral resource Statement

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2022 Mineral Resource and Mineral Reserve Statement

Rh

RHODIUM

Pt

PLATINUM

Pd

PALLADIUM

80 tharisa plc 2022 integrated annual report

MINERAL RESOURCE AND MINERAL RESERVE STATEMENT - THARISA MINERALS

Introduction

The Mineral Resource and Mineral Reserve of Tharisa Minerals was prepared under the guidance of the Competent Persons' (CP) in accordance with the requirements of the South African Code for the Reporting of Exploration Results, Mineral Resources and Mineral Reserves, 2016 (SAMREC Code). The estimates are as of

30 September 2022.

The previous declaration of the Mineral Resource and Mineral Reserve was dated September 2021. The current Mineral Resource declaration relies on the geological model and Mineral Resource model of April 2021 for the Middle Group (MG) Chromitite Layers, the Upper Group (UG) 1 Chromitite Layer and the end of Sep FY2022 mining faces. The Mineral Reserve declaration is based on the latest pit design and LOM schedule.

The data referenced in this section "Tharisa Minerals: Mineral Resource and Mineral Reserve Statement" is reported on a 100% basis.

Overview

Since the commencement of operations at the Tharisa Mine, additional geological information was obtained from geological observation in the operating pits and resource drilling. The Mineral Resource and Mineral Reserve information in the tables on the following pages are based on information compiled by the CPs.

Definitions

The declaration of the Mineral Resource and Reserve was undertaken in terms of the guidelines of SAMREC Code (2016 edition).

Location

The Tharisa Mine is located 35 km east of Rustenburg and 120 km northwest of Johannesburg in the North West Province of South Africa.

The Tharisa Mine is a mechanised open-pit operation.

Statement by Competent Person

Ken Lomberg of Pivot Mining Consultants Proprietary Limited (previously Coffey Mining South Africa Proprietary Limited) (Island House, Constantia Office Park, Cnr 14th Ave and Hendrik Potgieter Rd, Johannesburg, 1709), is the CP for the Mineral Resource declaration, and is registered with the South African Council for Natural Scientific Professions (Private Bag X540, Silverton, 0127, Gauteng province, South Africa), registration number 400038/01. He holds BSc (Hons) Geology, BCom and MEng (Mining Engineering) degrees. Mr Lomberg is a geologist with 38 years' experience, including the Mineral Resource estimation in respect of PGM and chromitite in the Bushveld Complex.

The Mineral Reserve was prepared under the supervision of Jaco Lotheringen of Ukwazi Mining Studies in his role as Mineral Reserve CP. He holds a BEng (Mining) degree. He is registered with the Engineering Council of South Africa (ECSA, Private Bag X691, Bruma, South Africa), registration number 20030022. The current address of the CP is Building C: Suite 1 - Level 04, The Gate Centurion,

130 Akkerboom Street, Zwartkop, Centurion, 0051. He is a principal mining engineer with appropriate experience in the estimation, assessment, and evaluation of relevant mineral reserves based on the class of deposit and mining methodology.

The Company has written confirmation from Messrs Lomberg and Lotheringen that the information disclosed is in compliance with the SAMREC Code (2016) and that they have consented to the inclusion of this information in the form and context in which it appears.

Mining rights summary

Tharisa Minerals holds a mining right, granted by the Department of Mineral Resources and Energy (DMRE) (then the Department of Minerals and Energy (DME) in terms of MPRDA on 19 September 2008, for a period of 30 years, to various portions of the farm 342 JQ and the whole of the farm Rooikoppies 297 JQ. On 13 August 2009, the mining right was registered in the Mining and Petroleum Titles Registration Office, under Reference No 49/2009(MR). In July 2011, an application was granted in terms of section 102 of the MPRDA, to amend the existing mining right by the addition of Portions 96,

183 and 286 of the property 342 JQ to the mining right 49/2009(MR). Such amendment was executed on 11 July 2011 and duly registered in the Mining and Petroleum Titles Registration Office.

Mineral Resource

Geology and mineralisation

The Tharisa Mine is situated on the southwestern limb of the Bushveld Complex, one of the world's largest layered mafic intrusions, which host layers rich in PGM, chromium and vanadium, and constitute the largest known resource of these metals. The Tharisa Mine is underlain by the MG and UG Chromitite Layers straddling the boundary between the Marikana and Rustenburg facies. The MG Chromitite Layers outcrop is on the property, striking roughly east to west, with a gentle change in strike to northwest-southeast in the far west. The layers dip at between 12° and 15° to the north. Towards the western extent of the outcrop, the dip is steeper. The stratigraphy typically narrows to the west and the dip steepens. The dip typically shallows out at depth across the extent of the mine area.

The MG Chromitite Layer package consists of five groups of Chromitite Layers, being the MG0 Chromitite Layer at the bottom, followed by the MG1 Chromitite Layer, the MG2 Chromitite Layer (sub-divided into A, B and C Chromitite Layers), the MG3 Chromitite Layer and the MG4 Chromitite Layer (sub-divided into 4(0), 4 and 4A Chromitite Layers). The layers between the Chromitite Layers frequently include stringers or disseminations of chromite. The MG Chromitite Layers at the Tharisa Mine are a typical stack of tabular deposits.

Figure 1: Location of the Tharisa Mine

MINERAL RESOURCE AND

MINERAL RESERVE STATEMENT

tharisa plc 2022 integrated annual report 81

44500 E

45000 E

45500 E

46000 E

46500 E

47000 E

47500 E

48000 E

48500 E

49000 E

49500 E

50000 E

50500 E

51000 E

51500 E

-2844000 N

-2844000 N

-2844500 N

Inferred

-2844500 N

-2845000 N

-2845000 N

-2845500 N

-2845500 N

N

-2846000 N

-2846000 N

Indicated

-2846500 N

-2846500 N

-2847000 N

Measured

-2847000 N

-2847500 N

Far-west Pit

-2847500 N

-2848000 N

East Pit

-2848000 N

0

500

1 000

1 500

2 000

2 500

47500 E

48000 E

48500 E

49000 E

49500 E

50000 E

50500 E

51000 E

51500 E

-2848500 N

Figure 2: Image of the Tharisa Mine plan showing borehole locations

The structural interpretation of the Tharisa Mine geology is based on the aeromagnetic data, the available drilling, and observations in the operating open pits. The only significant fault is a steeply dipping northwest-southeast trending normal fault with a downthrow of less than 30 m to the east. This fault occurs only on the far north-eastern corner of the property and will have little effect on mining of the MG Chromitite Layers on the mine. A northwest-southeastsub-vertical dyke of some 10 m thickness was exposed in the east pit. The dyke is not expected to have a major impact on mining. The other major feature of interest is the Spruitfontein upfold or pothole, which is located on the properties immediately west of the mine. It affects the UG2 Chromitite Layer and the rest of the critical zone below. No new major structural features were exposed by the current mining operation.

The Mineral Resource estimate was completed over the mining right of Tharisa Minerals to a depth of 750 m for the MG Chromitite Layers. The UG1 Chromitite Layer Mineral Resource estimate was limited to the area within the planned MG Chromitite pit perimeter.

The previous declaration of the Mineral Resource and Mineral Reserve was dated September 2021. The current Mineral Resource declaration relies on the geological model and resource model of April 2021 for the MG Chromitite Layers, the geological and resource model of June 2018 for the UG1 Chromitite Layer, and the end of FY2021 mining faces. Additional diamond drill boreholes were added to the database. Most significantly, the geological interpretation was reviewed with emphasis on the west and far-west pit areas. The geological interpretation includes the construction of three-dimensional models for each of the units estimated. Areas in the far west were redefined, where the individual layers were consolidated, requiring a revised perspective of the layer in the far-west mining area. Work on the area in the far west was largely responsible for the decrease in the reported tonnage of the Mineral Resource particularly in the Inferred category. The Mineral Resource, is restricted at a depth of 750 m below surface based on the "realistic expectations for eventual extraction".

The results from the samples confirmed the geological assumptions and the grades of the various Chromitite Layers, providing additional confidence in the mining operations. Observations on the operation confirm the details observed from the drilling. In-pit drilling continues for the purposes of mining operations, mine planning and grade control. Additional resource drilling has been planned for the next financial year.

Prior to the estimation, the data was collated and verified with the quality controls for logging, sampling, and assays being used. The Mineral Resource estimate was undertaken on each Chromitite Layer and interburden independently. Each element was estimated separately by inverse distance weighting (power2). The classification of the Mineral Resource is predominately determined by the distribution of the boreholes, with the consideration of the complexity of the geology, especially in the extreme western side of the property. Changes to the Mineral Resource declaration are due to the production during the previous financial year and a review of the MG3 Chromitite Layer in the Inferred area. The estimated thickness in these areas are slightly thinner in the areas mostly affecting the Indicated and Inferred Mineral Resources in these areas.

The Tharisa Minerals Resource at 31 September 2022 is reported inclusive of Mineral Reserve.

Figure 3: Stratigraphic map

82 tharisa plc 2022 integrated annual report

MINERAL RESOURCE AND MINERAL RESERVE STATEMENT - THARISA MINERALS continued

Figure 4: Map of the location of the Tharisa Mine

Mineral Resource estimate

2022	Unit	Measured	Indicated	Inferred	Total
Tonnes	Mt	102.81	109.26	637.51	849.58
6PGE + Au grade	g/t	1.77	1.43	1.55	1.56
5PGE + Au grade	g/t	1.69	1.36	1.47	1.48
3PGE + Au grade	g/t	1.32	1.03	1.14	1.15
Cr2O3 grade	%	22.44	19.42	19.78	20.05
Contained 6PGE + Au	Moz	5.84	5.02	31.68	42.54
Contained 5PGE + Au	Moz	5.63	4.48	30.41	40.52
Contained 3PGE + Au	Moz	4.37	3.61	23.32	31.30
Contained Cr2O3	Mt	23.07	21.22	126.08	170.37
2021	Unit	Measured	Indicated	Inferred	Total
Tonnes	Mt	109.16	112.56	632.68	854.40
6PGE + Au grade	g/t	1.77	1.41	1.53	1.54
5PGE + Au grade	g/t	1.69	1.35	1.45	1.47
3PGE + Au grade	g/t	1.33	1.02	1.12	1.13
Cr2O3 grade	%	22.42	19.37	19.72	20.02
Contained 6PGE + Au	Moz	6.21	5.11	31.06	42.39
Contained 5PGE + Au	Moz	5.99	4.47	29.80	40.26
Contained 3PGE + Au	Moz	4.65	3.68	22.81	31.15
Contained Cr2O3	Mt	24.47	21.80	124.79	171.06

MINERAL RESOURCE AND

MINERAL RESERVE STATEMENT

tharisa plc 2022 integrated annual report 83

Mineral Reserve estimate

Regulatory compliance

Mr Lotheringen is independent of Tharisa plc and Tharisa Minerals and has no direct or indirect interests in Tharisa plc or Tharisa Minerals. All work completed by Ukwazi for Tharisa plc was strictly in return for professional fees and payment for the work was not in any way dependent on the outcome thereof.

Mineral Reserve estimate

The Mineral Reserve estimate for September 2022 was based on a revised LOM plan for the open pits. This estimation was underpinned by an updated mining model and incorporates the current economic conditions, current on-mine mining methodology and actual surveyed depletion.

Appropriate technical aspects were considered in the mine design and schedule as the basis for the Mineral Reserve estimate, including economic pit limits, geotechnical parameters, mining methodology and sequence, pit access, ramp placement, equipment capability, production rates and practical mining considerations. The mining- related modifying factors applied included appropriate geological losses, mining losses and mining dilution. As part of the LOM process, a reconciliation was completed to establish a basis for the applied modifying factors that are considered appropriate to declare a Mineral Reserve.

Based on the reconciliation process, the mining related losses in the East pit was increased from 6% to 8%. Mining dilution for the East pit also increased by 6% on a cumulative thickness basis. Dilution and mining losses remained unchanged for the West pit year-on-year.

The mining losses and dilution applied for Far west pit, was confirmed.

The mining-related modifying factors applied per mining area are summarised in the table below.

Parameter		East	West	Far-west
Unit	pit	pit	pit
MG4A dilution
thickness	m	0.96	0.44	0.31
MG4 dilution thickness	m	1.04	0.83	0.58
MG3 dilution thickness	m	0.90	0.60	0.42
MG2 dilution thickness	m	0.91	0.71	0.50
MG1 dilution thickness	m	0.32	0.51	0.36
Cumulative dilution	m	4.13	3.09	2.17
Mining losses	%	8.0	6.0	10.0
Geological losses	%	5.0	7.5	15.0-25.0

The consolidated Mineral Reserve estimate decreased by 6.0 Mt as compared to the 2021 estimate. The main variances can be attributed to:

• Mining depletion that occurred during FY2022 of 5.4 Mt
• Confirmed and incremental dyke losses for FY2022 resulted in a decrease of 0.3 Mt
• Additional and incremental mining losses for FY2022 in the East pit due to the adjustment of mining practices while transitioning to lower selective mining methods resulted in a decrease of 0.9 Mt
• Revised mine design for the East Pit resulted in an increase of 1.9 Mt
• The geological model updates related to the revised reef outcrop position in the Western pits and the incremental geological loss

increase (from 15% to 25%) related to the IRUP area resulted in a decrease of 0.8 Mt

• Revision of mining related losses from 6% to 8% in the East pit accounted for a decrease of 1.5 Mt
• The incremental increase in dilution for the East pit resulted in an increase of 0.9 Mt

The LOM plan was designed to extract the MG Chromitite Layers, firstly from open pit mining to a maximum depth of 270 m below surface and subsequently from underground extraction (MG2 and MG4 Chromitite Layers) by means of a bord and pillar mining method. An underground mining pre-feasibility study was done during 2019 and subsequently updated for the 2021 Mineral Reserve estimate by removing selected areas that infringed the updated open pit economic limit.

The open-pit LOM plan was based on a targeted ROM production rate from both the East and the West open pits of 5.6 Mtpa over a period of 13 years before the production ramps down to depletion in 2040. Production transitions to underground mining from 2036 onwards.

No Inferred Mineral Resources were included in the open-pit LOM plan. Inferred Mineral Resources formed part of the underground LOM plan but not included in the Mineral Reserve estimate. Inferred Mineral Resources contributed approximately 87% of the underground LOM plan. If the Inferred Mineral Resources are excluded from the underground LOM plan, the underground project may not be feasible.

The underground operations were scheduled to ramp up during the final phase of the open pits, targeting the MG2 and MG4 Chromitite Layers. The Mineral Reserve for the underground section extends to a maximum depth of 270 m below surface, constrained by the estimated Measured and Indicated Mineral Resources. It is reasonable to expect that the underground LOM can be extended to a maximum depth of 750 m below surface, pending further exploration and associated technical study work.

A detailed LOM plan was completed to declare the Mineral Reserve estimate for the surface mining operations, based on the geological model used as basis for the Mineral Resource estimate.