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Reserves & Resources

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Mineral Resources

The Mineral Resource was estimated using a combination of ordinary kriging and multiple indicator kriging of element grades into detailed geology model volumes of the respective nickel laterite domains. Dry bulk density values were assigned to the models based on core based values (caliper method) or in selected areas of the Shoemaker-Levy deposits, downhole geophysics.

The models were depleted for mining (where relevant) and reported using a 0.3% nickel cut-off grade. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Fe, Al, Mg and Ca estimates do not constitute part of the Mineral Resource or Mineral Reserve. They are included as additional information relevant to beneficiation and leaching performance.

Mineral Resource inclusive of stockpiles - as at December 31, 2021, cut-off grade 0.3% Ni

Deposit Classification Tonnes (Mt) Ni (%) Co (%) Fe (%) Al (%) Mg (%) Ca (%) CO3 (%) Cu (g/t) Zn (g/t)
Halleys Measured 2.4 0.61 0.03 11.75 1.69 5.61 1.60 - 30.00 80.00
Indicated 2.6 0.56 0.03 13.48 2.79 6.28 0.99 - 60.00 80.00
Total Meas. plus Ind. 5.0 0.58 0.03 12.64 2.26 5.95 1.29 - 45.45 80.00
Inferred 0.3 0.61 0.03 10.60 1.25 9.69 1.80 - 30.00 80.00
Hale-Bopp Measured 21.7 0.55 0.03 11.83 1.51 5.52 0.52 - 20.00 60.00
Indicated 15.4 0.55 0.03 11.50 1.65 8.04 0.77 - 40.00 70.00
Total Meas. plus Ind. 37.0 0.55 0.03 11.69 1.57 6.57 0.62 - 28.31 64.15
Inferred 1.2 0.47 0.02 9.51 1.73 10.71 1.49 - 30.00 80.00
Shoemaker-Levy Measured 80.6 0.58 0.03 12.71 1.24 3.50 1.93 - 30.00 80.00
Indicated 102.2 0.55 0.03 12.50 1.64 4.13 1.53 - 40.00 100.00
Total Meas. plus Ind. 182.7 0.56 0.03 12.59 1.46 3.85 1.71 - 35.59 91.18
Inferred 9.6 0.47 0.02 10.76 1.27 6.87 2.69 - 40.00 80.00
Nindilbillup Inferred 26.7 0.53 0.03 12.93 2.38 5.82 0.38 - 80.00 120.00
Shoemaker-Levy North Inferred 30.5 0.52 0.02 11.20 2.71 3.32 0.79 - 40.00 70.00
Total Resources Total Measured 104.6 0.57 0.03 12.51 1.31 3.97 1.63 - 27.93 75.86
Total Indicated 120.2 0.55 0.03 12.39 1.67 4.68 1.42 - 40.43 95.73
Total Meas. plus Ind. 224.8 0.56 0.03 12.45 1.50 4.35 1.52 - 34.61 86.48
Total Inferred 68.3 0.52 0.02 11.78 2.36 4.95 0.91 - 55.44 91.19
Stockpiled Resources Measured 17.7 0.58 0.03 11.18 1.32 5.20 1.30 8.60 - -

This December 31, 2021 Mineral Resource estimate has been prepared by independent consultant and qualified person, Richard Sulway (QP) MAppSc (Geological data processing), BAppSc (Hons, Applied Geology), MAusIMM (CP), Consulting Geologist, FQM (Australia) Pty Ltd and verified by David Gray (QP) BSc(Hons, Geology), MAusIMM, FAIG, Group Mine and Resource Geologist, FQM (Australia) Pty Ltd.

Mineral Reserves

The Mineral Reserve for RNO inclusive of stockpiles, as at December 31, 2021, is presented in the following table. The life of mine Mineral Reserve is defined using a a 0.3% nickel cut-off grade. The estimate is derived from conventional optimization processes, detailed stage and ultimate pit designs and life of mine production scheduling. Mg and Ca estimates do not constitute part of the Mineral Resource or Mineral Reserve. They are included as additional information relevant to beneficiation and leaching performance.

In addition to the stockpiles there is also an intermediate beneficiated product that is held within the processing surge (buffer) ponds. At the end of December 2021 the quantity of this material (considered as Proven Reserve) was 81,000 tonnes @ 1.00%Ni.

At the current throughput rate the remaining life of mine is 19 years.

Mineral Reserves - as at December 31, 2021, and reported based on a 0.3% nickel cut-off grade

Classification Ore (Mt) Ni (%) Co (%) Ca (%) Mg (%)
Limonite Ore
Total Proven 67.2 0.62 0.03 0.6 2.1
Total Probable 62.9 0.60 0.03 0.5 2.0
Total Mineral Reserves 130.0 0.61 0.03 0.6 2.1
Saprolite Ore
Total Proven 24.2 0.44 0.02 4.4 7.5
Total Probable 23.7 0.46 0.02 3.5 8.2
Total Mineral Reserves 48.0 0.45 0.02 3.9 7.9
Total Ore in Pits
Total Proven 91.4 0.57 0.03 1.6 3.6
Total Probable 86.6 0.56 0.03 1.4 3.7
Total Mineral Reserves 178.0 0.56 0.03 1.5 3.6
Stockpile
Total Proven 17.7 0.58 0.02 1.5 9.4
Total Probable - - - - -
Total Mineral Reserves 17.7 0.58 0.02 1.5 9.4
Reserve including Stockpile
Total Proven 109.1 0.57 0.03 1.6 4.5
Total Probable 86.6 0.56 0.03 1.4 3.7
Total Mineral Reserves 195.7 0.57 0.03 1.5 4.1

This Mineral Reserve estimate as at December 31, 2021, has been prepared and verified by independent consulting Mining Engineer, Anthony Cameron of Cameron Mining Consulting Ltd. Anthony Cameron is a qualified person and holds the following valid qualifications: BE (Mining), Grad Dip Bus, M Comm. Law, FAusIMM