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Mineral Resources and Ore Reserve Estimate

Mineral Resource Estimate

Mineral Resource estimates for Zeta NE, Zone 5 North and Mango NE were completed using Hexagon Mining’s HxGN MinePlan 3D while Zone 5 and Banana Zone and other resources were completed using using MineSight software all in UTM coordinates. A resource classification procedure defined by the number of drill holes and average distances to composites was used to classify blocks as Measured, Indicated or Inferred.

For Measured classification, blocks used at least three drill holes where the average distance to the composites was within 55m. For Indicated classification, blocks used at least three drill holes with the closest composite within 60m or the average distance of the three holes composite was within 95m (Zone 5 is 95m) to 140m, dependant on the deposit. For Inferred classification, at least two drill holes with the closest drill hole less than 150m was required. Where continuity allowed, Inferred classification was allowed to carry along strike where shallow drilling is approximately 400m.

The Resource estimates were prepared in accordance with the guidelines set out in the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reservices (the JORC Code) 2012 edition.

The consolidated Khoemacau/Boseto package provides Khoemacau a near-term opportunity for low cost copper production from a long-lived operation with substantial exploration and production upside. The following table represents total resources on the mining and prospecting permitted properties:

ResourceMeasuredIndicatedInferredTotal (MI&I)Contained MetalReportedCutoff Copper %
Tonnes (Mt)Copper %Silver g/tTonnes (Mt)Copper %Silver g/tTonnes (Mt)Copper %Silver g/tTonnes (Mt)Copper %Silver g/tCopper Tonnes (Mt)Silver Ounces (Moz)  
Zone 5 High Grade Sulphide 16.5 2.4 22.2 26.2 2.2 21.1 49.6 2.1 22.6 92.4 2.2 22.1 2.0 65.6 Jun‑2020 1.0
Zeta NE High Grade Sulphide       8.9 2.6 53.4 20.0 1.8 33.6 29.0 2.0 39.7 0.6 37.0 Nov‑2020 1.0
Zone 5 North High Grade Sulphide       4.5 2.6 44.5 21.2 2.1 36.6 25.6 2.2 38.0 0.6 31.3 Sept‑2019 1.0
Mango NE High Grade Sulphide       11.4 1.9 22.7 9.6 1.7 19.7 21.1 1.8 21.3 0.4 14.8 Aug‑2021 1.0
Banana & Other Resources   8.3 1.3 16.2 39.4 1.2 16.8 287.6 0.9 11.2 335.4 1.0 11.7 3.3 126.5 Aug‑2014 0.5
Total   24.9 2.0 20.2 90.0 1.8 23.6 389.0 1.2 15.4 503.9 1.4 17.0 6.9 275.2    

Zone 5

Over 253,000 meters of drilling have been completed by Khoemacau since 2013 and previous operators at Zone 5, which has MI&I sulphide resources at a 1.0% Cu cut-off of 92.4 million tonnes @ 2.2% Cu and 22.1 g/t Ag (~46% of the tonnes and contained metal are measured & indicated). The mineralization is predominately bornite, chalcocite, and chalcopyrite.

Zone 5
Zone 5 long section Life Of Mine (LOM) mineral resource classification (Note: View is looking from the hanging wall (HW) to the plane of the orezone)

The following table shows the Zone 5 mineral resource MI&I classification as of June 2020 (1% Cu cut-off):

ClassificationMillion Tonnes (Mt)Cu (%)Ag (g/t)
Measured 16.5 2.4 22.2
Indicated 26.2 2.2 21.2
Inferred 49.7 2.1 22.6
Total 92.4 2.2 22.1

Note: Mineral Resources are reported in accordance with the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (The Joint Ore Reserves Committee Code – JORC 2012 Edition)

Zone 5 North

Total copper, silver, molybdenum, lead, zinc, and arsenic were estimated into blocks using Ordinary Kriging (OK) interpolation with Dynamic Unfolding. Inverse Distance Weighted (IDW) interpolation was used to estimate acid soluble to total copper ratio, cyanide soluble to total copper ratio, and density.

The drill hole database used for the September 2019 resource model included 47 core holes and 10 RC holes.

Zone 5 North
Zone 5 North long section Life Of Mine (LOM) mineral resource classification (Note: View is looking from the hanging wall (HW) to the plane of the orezone )

Three-dimensional wireframes based on geology, mineral content and copper grade were used to constrain the interpolation of grades in the block model. The block model used a 10 x 2 x 2m block in the X, Y and Z directions and is sub-blocked along the domain boundaries to a minimum size of 1 x 1 x 1m.

The Zone 5 North Mineral Resource, using a 1% Cu cut-off and constrained within the high-grade wireframe (Grade Zone 30) is presented in the following table:

ClassificationMillion Tonnes (Mt)Cu (%)Ag (g/t)
Measured - - -
Indicated 4.5 2.6 44.5
Inferred 21.2 2.1 36.6
Total 25.6 2.2 38.0

Note: Mineral Resources are reported in accordance with the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (The Joint Ore Reserves Committee Code – JORC 2012 Edition)

Zeta NE

Total copper, silver, molybdenum, lead, zinc and arsenic were estimated into blocks using Ordinary Kriging. Acid soluble copper to total copper ratios, cyanide soluble to total copper ratio, and density were estimated using Inverse Distance Weighted (IDW) Squared interpolation.

The drill hole database used for the November 2020 resource model included 224 drill holes, of which 158 were used to define the copper grade domains.

Zeta  NE
Zeta NE long section Life Of Mine (LOM) mineral resource classification (Note: View is looking from the hanging wall (HW) to the plane of the orezone)

Three-dimensional wireframes were created for two high-grade copper domains, a hanging wall (GZ31) and footwall (GZ32). The block model used a 10 x 2 x 2m block in the X, Y and Z directions and is sub-blocked along the domain boundaries to a minimum size of 1 x 1 x 1m.

The Zeta NE Mineral Resource, using a 1% Cu cut-off and constrained within the high-grade wireframes (Grade Zone 31 and 32) is presented in the following table:

ClassificationMillion Tonnes (Mt)Cu (%)Ag (g/t)
Indicated GZ 31 3.0 2.7 52.0
Indicated GZ 32 5.9 2.5 54.1
Inferred GZ 31 1.3 2.1 33.7
Inferred GZ 32 18.7 1.7 33.6
Total 28.9 2.0 39.7

Note: Mineral Resources are reported in accordance with the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (The Joint Ore Reserves Committee Code – JORC 2012 Edition)

Mango NE

Total copper and silver were estimated into blocks using Ordinary Kriging. Molybdemum, lead, zinc, arsenic, soluble copper to total copper ratios, and densities were estimated using Inverse Distance Weighting (IDW) Squared interpolation.

The drill hole database used for the January 2020 resource model included 110 drill holes, of which 70 were used to define the copper grade domains.

Mango NE
Mango NE long section Life Of Mine (LOM) mineral resource classification (Note: View is looking from the hanging wall (HW) to the plane of the orezone)

Three-dimensional wireframes were created for two high-grade copper domains, a hanging wall (GZ31) and footwall (GZ32). The block model used a 10 x 5 x 5m block in the X, Y and Z directions and is sub-blocked along the domain boundaries to a minimum size of 1 x 1 x 1m.

The Mango Mineral Resource, using a 1% Cu cut-off and constrained within the high-grade wireframes is presented in the following table:

ClassificationMillion Tonnes (Mt)Cu (%)Ag (g/t)
Indicated GZ 31 4.5 1.6 9.1
Indicated GZ 32 7.0 2.1 31.4
Inferred GZ 31 3.1 1.5 8.4
Inferred GZ 32 6.5 1.9 25.0
Total 21.1 1.8 21.3

Note: Mineral Resources are reported in accordance with the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (The Joint Ore Reserves Committee Code – JORC 2012 Edition)

Banana Zone

The Banana Zone Mineral Resource estimate was completed using MineSight software in UTM coordinates. The last resource was reported 06 August 2014. A resource classification procedure defined by the number of drill holes and average distances to composites used was designed to classify blocks as Measured, Indicated or Inferred. For Measured classification, blocks used at least three drill holes with the average distance of the three holes composite was within 75m. For Indicated classification, blocks used at least three drill holes with the closest composite within 75m or the average distance of the three holes composite was within 150m. For Inferred classification, at least two drill holes with the closest drill hole less than 150m was required.

Three-dimensional wireframes based on geology, mineral continuity, mineralogy, and copper grade were used to constrain the interpolation of grades in the block model. Five resource models were built to cover the Banana Zone. This included four detailed models with smaller blocks and closer spaced drilling (using blocks ranging from 5 x 3 x 4m to 10 x 5 x 5m) and one model for the entire Banana Zone with larger blocks to cover the wider spaced drilling (using blocks 40 x 6 x 4m in the X, Y and Z directions). The detailed models include North East Fold, New Discovery, South Limb and South Limb Definition.

Total copper, silver, molybdenum, lead, zinc, arsenic, acid soluble to total copper ratio, cyanide soluble to total copper ratio, and density were all estimated into blocks using Inverse Distance Weighted interpolation. The North East Fold model used Dynamic Unfolding.

The drill hole database used for the August 2014 resource model included 580 core and 451 RC holes.

The Banana Zone Total Mineral Resource, using a 0.5% Cu cut-off and constrained within the wireframes is presented in the following table:

ResourcesMeasuredIndicatedInferredTotal (MI&I)
 Tonnes (Mt)Copper %Silver g/tTonnes (Mt)Copper %Silver g/tTonnes (Mt)Copper %Silver g/tTonnes (Mt)Copper %Silver g/t
North East Fold 1.0 1.15 19.0 7.2 1.13 18.0 8.4 1.10 17.0 16.6 1.12 17.6
New Discovery       7.9 1.20 19.7 10.6 0.85 13.0 18.5 1.00 15.9
South Limb Definition       3.7 1.17 16.6 8.9 1.28 19.0 12.6 1.25 18.3
South Limb             8.1 0.97 12.0 8.1 0.97 12.0
Chalcocite             32.7 0.64 6.0 32.7 0.64 6.0
Banana Zone             98.8 0.71 8.7 98.8 0.71 8.7
Total 1.0 1.2 19.0 18.8 1.7 21.7 167.3 1.3 16.1 187.2 0.8 10.5

The Banana Zone Mineral Resource for high grade deposits only, using a 0.5% Cu cut-off and constrained within the high-grade wireframes is presented in the following table:

ResourcesMeasuredIndicatedInferredTotal (MI&I)
 Tonnes (Mt)Copper %Silver g/tTonnes (Mt)Copper %Silver g/tTonnes (Mt)Copper %Silver g/tTonnes (Mt)Copper %Silver g/t
North East Fold 1.0 1.15 19.0 7.2 1.13 18.0 8.4 1.10 17.0 16.6 1.12 17.6
New Discovery       7.9 1.20 19.7 10.6 0.85 13.0 18.5 1.00 15.9
South Limb Definition       3.7 1.17 16.6 8.9 1.28 19.0 12.6 1.25 18.3
South Limb             8.1 0.97 12.0 8.1 0.97 12.0
Total 1.0 1.2 19 18.8 1.7 21.7 35.9 1.3 16.1 55.8 1.1 16.4

Ore Reserve Estimate

As of 30th June 2020, the ore reserve estimate for the Khoemacau Zone 5 +60kt Copper/Silver Starter Project is 33.96 million tonnes at 2.03% Copper and 19.66g/t Silver and is in accordance with the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC code) 2012 edition. The following table summarises the total reportable Ore Reserves at the Zone 5 +60kt Copper/Silver Starter Project as of the 30th June 2020 and at a Cu price of US$3/lb ,and an Ag price of US$17.50/oz.

CategoryOre Tonnes (Mt)Cu %Cu (kt)Ag (g/t)Ag (Moz)
Proven 11.03 2.19 241.38 20.72 7.35
Probable 22.93 1.95 447.37 19.15 14.12
Total 33.96 2.03 688.75 19.66 21.47

The Zone 5 LOM plan will include additional material from the inferred mineral resource category, to give a better indication of expected mine life. The following table summarises the additional material that will be included in the LOM plans but has not yet been classified with sufficient confidence for reporting purposes:

CategoryOre Tonnes (Mt)Cu %Cu (kt)Ag (g/t)Ag (Moz)
Inferred 41.02 1.98 813.48 22.06 29.09
Total 74.98 2.00 1,502.23 20.97 50.56

The following figure is the 2020 LOM schedule coloured by Ore Reserve categories:

2020 LOM schedule
Zone 5 Long section Life Of Mine (LOM) Ore Reserve classification (Note: View is looking from the hanging wall (HW) to the plane of the orezone)