Current mineral reserves and resources (exclusive of reserves) for Rosemont are summarized below.

Rosemont Project
Mineral Reserve and Resource Estimates1
Tonnes Cu Grade
(%)
Mo Grade
(%)
Ag Grade
(g/t)
Mineral Reserves2,3
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
Mineral Resources 3
Measured 161,300,000 0.38 0.009 2.72
Indicated 374,900,000 0.25 0.011 2.60
Total measured and indicated 536,200,000 0.29 0.011 2.64
Inferred 62,300,000 0.30 0.010 1.58

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

1 Based on 100% ownership of the Rosemont project.

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

3 Mineral reserves and resources calculated using metal prices of $3.15 per pound copper, $11.00 per pound molybdenum and $18.00 per ounce silver.

Current mineral reserves and resources (exclusive of reserves) for Constancia as of January 1, 2019 are summarized below.

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 421,800,000 0.30 94 0.035 2.87
Probable 72,000,000 0.23 72 0.035 3.06
Total proven and probable - Constancia 493,800,000 0.29 91 0.035 2.90
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 533,700,000 0.31 97 0.059 3.03
Constancia Resources
Measured 169,400,000 0.18 50 0.028 2.19
Indicated 180,500,000 0.20 56 0.034 2.16
Inferred 50,800,000 0.24 43 0.046 2.41
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 367,300,000 0.20 55 0.042 2.31
Total inferred 60,900,000 0.22 60 0.077 2.65

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

1 Mineral reserves and resources calculated using metal prices of $3.00 per pound copper, $11.00 per pound molybdenum, $18.00 per ounce silver and $1,260 per ounce gold.

Current mineral reserves and resources (exclusive of reserves) for Lalor as of January 1, 2019 are summarized below.

Lalor Mine
Mineral Reserve and Resource Estimates1
Tonnes Cu Grade
(%)
Zn Grade
(%)
Au Grade
(g/t)
Ag Grade
(g/t)
Base Metal Zone Reserves
Proven 5,137,000 0.76 7.13 2.37 26.31
Probable 5,552,000 0.44 4.19 3.52 27.39
Gold Zone Reserves
Proven 58,000 0.80 2.65 5.46 39.09
Probable 2,928,000 1.09 0.31 6.74 23.08
Total proven and probable 13,675,000 0.70 4.46 3.78 26.11
Base Metal Zone Resources
Inferred 1,385,000 0.70 2.30 4.49 43.58
Gold Zone Resources
Inferred 4,516,000 1.08 0.35 4.38 20.42
Total inferred 5,901,000 0.99 0.81 4.41 25.85

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

1 Mineral reserves and resources calculated using metal prices of $1.17 per pound zinc (includes premium), $1,260 per ounce gold, $3.10 per pound copper, $18.00 per ounce of silver and using a C$/US$ exchange rate of 1.25.

Current mineral resources for the Snow Lake regional deposits as of January 1, 2019 are summarized below.

Snow Lake Regional Deposits (Excluding Lalor)
Mineral Resource Estimates1,2,3
Category Tonnes Cu (%) Zn (%) Au (g/t) Ag (g/t)
WIM Indicated 3,900,000 1.71 0.26 1.57 6.68
Inferred 700,000 1.03 0.37 1.76 4.65
Pen II Indicated 500,000 0.49 8.89 0.35 6.81
Inferred 100,000 0.37 9.81 0.30 6.85
New Britannia Zones Inferred (Gold) 4,500,000 - - 4.82 -

1 WIM mineral resources reported based on a 1.3% CuEq cut-off for the underground portion, and a 0.5% cut-off for the open pit portion, assuming processing recoveries of 90% for copper and zinc for gold and silver, and using long-term prices of $3.00 per pound copper, $1,200 per ounce gold, $1.00 per ounce zinc and $15.00 per ounce of silver.

2 Pen II mineral resources are estimated at a minimum NSR cut-off of C$65 per tonne and assumed that the Pen II mineral resources would be amenable to processing at the Stall mill.

3 New Britannia mineral resource estimates have been reported at a minimal true width of 1.5 metres and with a cut-off grade varying from 2 grams per tonne (at the 3 Zone and the lower part of New Britannia zone) to 3.3 grams per tonne (at Birch and for the upper part of New Britannia zone).

Current mineral reserves and resources (exclusive of reserves) for 777 as of January 1, 2019 are summarized below.

777 Mine
Mineral Reserve and Resource Estimates1
Tonnes Cu Grade
(%)
Zn Grade
(%)
Au Grade
(g/t)
Ag Grade
(g/t)
Mineral Reserves
Proven 2,169,000 1.80 4.44 1.77 26.45
Probable 1,384,000 0.97 3.75 2.03 21.65
Total proven and probable 3,552,000 1.48 4.17 1.87 24.58
Mineral Resources
Indicated 375,000 1.13 4.05 1.79 29.57
Inferred 395,000 1.43 5.03 3.09 40.44

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

1 Mineral reserves and resources calculated using metal prices of $3.10 per pound copper, $1.24 per pound zinc (includes premium), $1,283 per ounce gold, $17.50 per ounce silver and using a C$/US$ exchange rate of 1.267.

Current mineral resources for the Ann Mason regional deposits are summarized below.

Category 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
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.