Lalor Mine


Mineral Reserve and Resource Estimates1,2,3,4
Tonnes Cu Grade
(%)
Zn Grade
(%)
Au Grade
(g/t)
Ag Grade
(g/t)
Base Metal Zone Reserves
Proven 7,276,000 0.57 6.27 2.42 29
Probable 1,739,000 0.60 4.15 3.83 31
Gold Zone Reserves
Proven 1,748,000 1.37 1.11 6.70 24
Probable 4,251,000 0.83 0.42 6.21 27
Total proven and probable 15,015,000 0.74 3.77 4.16 28
Base Metal Zone Resources
Inferred 454,000 0.34 7.32 2.16 21
Gold Zone Resources
Inferred 3,945,000 1.31 0.31 4.69 26
Total inferred 4,399,000 1.21 1.03 4.43 26

Note: totals may not add up correctly due to rounding.

1 Mineral resources are exclusive of mineral reserves and do not have demonstrated economic viability.
2 Mineral reserves and resources calculated using metal prices of $1.17 per pound zinc (includes premium), $1,375 per ounce gold, $3.10 per pound copper, $17.00 per ounce of silver.
3 Mineral reserves are estimated at an NSR cut-off of $101 per tonne for waste filled mining areas and a minimum of $113 per tonne for paste filled mining areas.
4 Mineral resources are estimated at a minimum NSR cut-off of $101 per tonne.

Snow Lake Regional Deposits - Gold


Mineral Reserve and Resource Estimates
Tonnes Cu (%) Zn (%) Au (g/t) Ag (g/t)
Probable Reserves1
WIM 2,448,000 1.63 0.25 1.6 6.3
3 Zone 662,000 - - 4.2 -
Total Probable (Gold) 3,110,000 1.28 0.20 2.2 5.0
Inferred Resources2
Birch 569,000 - - 4.4 -
New Britannia 2,753,000 - - 4.5 -
Total Inferred (Gold) 3,222,000 - - 4.5 -

Note: totals may not add up correctly due to rounding.

1 WIM mineral reserves are estimated at a minimum net smelter return (“NSR”) cut-off of C$150 per tonne, assuming processing recoveries of 98% for copper, 88% for gold and 70% for silver, and using long-term prices of $3.10 per pound copper, $1,375 per ounce gold and $17.00 per ounce silver. 3 Zone mineral reserves are estimated at a minimum NSR cut-off of C$150 per tonne, assuming processing recoveries of 85% for gold, and using a long-term price of $1,375 per ounce gold.
2 Mineral resources are exclusive of mineral reserves and do not have demonstrated economic viability. New Britannia mineral resource estimates have been reported at a minimum true width of 1.5 metres and with a cut-off grade varying from 2 grams per tonne (at the lower part of New Britannia) to 3.5 grams per tonne (at the upper part of New Britannia).

Snow Lake Regional Deposits - Base Metals


Mineral Reserve and Resource Estimates1
Tonnes Cu (%) Zn (%) Au (g/t) Ag (g/t)
Indicated Resources
Pen II 469,000 0.49 8.89 0.35 6.8
Total Indicated (Base Metals) 469,000 0.49 8.89 0.35 6.8
Inferred Resources
Watts 3,153,000 2.34 2.58 0.95 31
Pen II 132,000 0.37 9.81 0.3 6.9
Total Inferred (Base Metals) 5,350,000 1.48 5.49 0.9 30.1

Note: totals may not add up correctly due to rounding.

1 Mineral resources are exclusive of mineral reserves and do not have demonstrated economic viability. 1901 mineral resources are estimated at a minimum NSR cut-off of $170 per tonne, assuming processing recoveries of 73% for copper, 94% for zinc, 48% for gold and 47% for silver, and using long-term prices of $3.10 per pound copper, $1,260 per ounce gold, $1.10 per pound zinc and $18.00 per ounce silver. Watts mineral resources are estimated at a minimum NSR cut-off of $150 per tonne, assuming processing recoveries of 87% for copper, 80% for zinc, 65% for gold and 64% for silver, and using long-term prices of $3.10 per pound copper, $1,375 per ounce gold, $1.10 per pound zinc and $17.00 per ounce silver. Pen II mineral resources are estimated at a minimum NSR cut-off of $75 per tonne and assume that the Pen II mineral resources would be amenable to processing at the Stall mill.

1901 Deposit Mineral Resource Estimates1,2,3,4,5


2020 Mineral Resource Estimates
Tonnes Zn Grade (%) Au Grade (g/t) Ag (g/t) Cu Grade (%)
Base Metal Zone
Measured 980,000 6.79 2.2 29.9 0.43
Indicated 1,090,000 10.07 1.5 32.9 0.30
Total Measured and Indicated 2,070,000 8.52 1.8 31.5 0.36
Inferred 355,000 7.11 1.8 24.4 0.79
Gold Zone
Inferred 535,000 0.53 6.8 36.0 0.78

1CIM definitions were followed for the estimation of mineral resources. Mineral resources that are not mineral reserves do not have demonstrated economic viability.

2Mineral resources are reported within an economic envelope defined by a mineral stope optimization algorithm assuming a selective mining method.

3Long-term metal prices of $1,500/oz gold, $18.00/oz silver, $3.00/lb copper and $1.09/lb zinc were used for the estimation of the mineral resources.

4Metal recovery estimates are based on the assumption that the base metal mineralization would be processed at Hudbay’s Stall concentrator and would present a similar performance to those experienced historically for the Chisel and Lalor zinc-rich lenses. The gold mineralization is assumed to be processed at the New Britannia concentrator, which is currently being refurbished.

5 Specific gravity measurements using industry standard techniques were completed on all assayed intervals.

777 Mine


Mineral Reserve and Resource Estimates1
Tonnes Cu Grade
(%)
Zn Grade
(%)
Au Grade
(g/t)
Ag Grade
(g/t)
Mineral Reserves
Proven 2,122,000 1.44 4.55 2.01 27
Probable 459,000 1.11 4.11 1.75 26
Total proven and probable 2,581,000 1.38 4.47 1.96 27
Mineral Resources
Measured 370,000 2.02 3.69 1.97 25
Indicated 140,000 1.02 3.85 1.57 26
Total Measured and Indicated 510,000 1.75 3.74 1.86 26
Inferred 210,000 1.48 5.22 3.11 40

Note: totals may not add up correctly due to rounding.

1 Mineral resources are exclusive of mineral reserves and do not have demonstrated economic viability. Mineral reserves and resources calculated using life-of-mine (2020-2022) average metal prices of $2.92 per pound copper, $1.11 per pound zinc (includes premium), $1,392 per ounce gold, $16.33 per ounce silver and using a C$/US$ exchange rate of 1.30.

Constancia Mine


Mineral Reserve and Resource Estimates1
Tonnes Cu Grade
(%)
Mo Grade
(g/t)
Au Grade
(g/t)
Ag Grade
(g/t)
Constancia Reserves
Proven 408,800,000 0.28 85 0.035 2.76
Probable 77,500,000 0.27 70 0.044 3.58
Total proven and probable - Constancia 486,300,000 0.28 83 0.036 2.89
Pampacancha Reserves
Proven 32,400,000 0.59 178 0.368 4.48
Probable 7,500,000 0.62 173 0.325 5.75
Total proven and probable - Pampacancha 39,900,000 0.60 177 0.360 4.72
Total proven and probable 526,600,000 0.30 90 0.061 3.03
Constancia Resources
Measured 122,700,000 0.18 55 0.028 1.77
Indicated 154,300,000 0.20 65 0.033 1.87
Inferred 83,100,000 0.18 43 0.036 3.39
Pampacancha Resources
Measured 11,400,000 0.41 101 0.245 4.95
Indicated 6,000,000 0.35 84 0.285 5.16
Inferred 10,100,000 0.14 143 0.233 3.86
Total measured and indicated 294,400,000 0.20 63 0.045 2.01
Total inferred 93,200,000 0.18 54 0.057 3.44

Note: totals may not add up correctly due to rounding.

1 Mineral resources are exclusive of mineral reserves and do not have demonstrated economic viability. Mineral reserves and resources calculated using metal prices of $3.10 per pound copper, $11.00 per pound molybdenum, $17.00 per ounce silver and $1,375 per ounce gold. The Constancia and Pampacancha reserve pits consist of operational pits of proven and probable reserves and are based on metal prices noted, metallurgical recoveries applied by ore type (between 84.4% to 90.5%), and processing costs of $4.54 per tonne milled, general and administrative costs of $1.60 per tonne milled and mining costs of $1.30 and $1.35 per tonne moved (waste and ore, respectively).

Rosemont Project


Mineral Reserve Estimates(1)(2)(3)
Tonnes Cu
(%)
Mo
(%)
Ag
(g/t)
Proven 426,100,000 0.48 0.012 4.96
Probable 111,000,000 0.31 0.010 3.09
Total proven and probable 537,100,000 0.45 0.012 4.58

Note: totals may not add up correctly due to rounding.

1 Blocks were classified as Proven or Probable in accordance with CIM Definition Standards 2014

2 Mineral resources are constrained within a computer generated pit using the Lerchs-Grossman algorithm. Metal prices of US$3.15 per pound copper, US$11.00 per pound molybdenum and US$18.00 per ounce of silver were used. Metallurgical recoveries of 90% copper, 63% molybdenum and 75.5% silver were applied. No metallurgical recovery of molybdenum and silver from oxide ore is projected.

3 Based on 100% ownership of the Rosemont project.

Mineral Resource Estimates(1)(2)(3) Tonnes Cu
(%)
Mo
(%)
Ag
(g/t)
Measured 161,300,000 0.38 0.009 2.72
Indicated 374,900,000 0.25 0.011 2.60
Total Measured & Indicated 536,200,000 0.29 0.011 2.64
Total Inferred 62,300,000 0.30 0.010 1.58

1 Mineral resources that are not mineral reserves do not have demonstrated economic viability. Please refer to Schedule A “Glossary of Mining Terms” in our Annual Information form dated March 29, 2020.

2 Mineral resources are constrained within a computer generated pit using the Lerchs-Grossman algorithm. Estimates of mineral resources are based on the following long-term metals prices: $3.15 per pound of copper; $11.00 per pound of molybdenum; and $18.00 per ounce of silver. Metallurgical recoveries of 85% copper, 60% molybdenum and 75% silver were applied to sulfide material. Metallurgical recoveries of 40% copper, 30% molybdenum and 40% silver were applied to mixed material. A metallurgical recovery of 65% for copper was applied to oxide material. NSR was calculated for every model block and is an estimate of recovered economic value of copper, molybdenum, and silver combined. Cut-off grades were set in terms of NSR based on current estimates of process recoveries, total processing and general and administrative operating costs of $5.70 per ton for oxide, mixed and sulfide material.

3 Based on 100% ownership of the Rosemont project.

Mason Project


Mineral Resource Estimates(1)(2)
Tonnes Cu
(%)
Au
(g/t)
Ag
(g/t)
Mo
(%)
Measured & Indicated 1,400,000,000 0.32 0.03 0.65 0.006
Inferred 623,000,000 0.29 0.03 0.66 0.007

1 Mineral resources that are not mineral reserves do not have demonstrated economic viability.

2 For additional details relating to the estimates of mineral resources at the Mason project, refer to the technical report dated March 3, 2017 and filed on SEDAR by Mason Resources Corp.

Qualified Person

The technical and scientific information contained on this website related to the Constancia mine and Rosemont project has been approved by Cashel Meagher, P. Geo, Hudbay’s Senior Vice President and Chief Operating Officer. The technical and scientific information related to the company’s other material mineral projects contained on this website has been approved by Olivier Tavchandjian, P. Geo, Hudbay’s Vice-President Exploration and Geology. Messrs. Meagher and Tavchandjian are qualified persons pursuant to NI 43 101. For a description of the key assumptions, parameters and methods used to estimate mineral reserves and resources at Hudbay’s material properties, as well as data verification procedures and a general discussion of the extent to which the estimates of scientific and technical information may be affected by any known environmental, permitting, legal title, taxation, sociopolitical, marketing or other relevant factors, please see the technical reports for the company’s material properties as filed by Hudbay on SEDAR at www.sedar.com.