Hudbay’s US properties are the Copper World and Rosemont projects, located in Arizona, and the Mason project, located in Nevada.

Copper World was discovered in 2021 and is located on our wholly-owned patented mining claims and within seven kilometres of our Rosemont project. The drill program that lead to this discovery was initiated in 2020 to confirm historic drilling and after receiving encouraging initial results, launched a larger drill program in 2021, which resulted in an initial mineral resource estimate.

Indicated mineral resources of 272 million tonnes at 0.36% copper and inferred mineral resources of 142 million tonnes at 0.36% copper, which includes near surface, higher grade indicated mineral resources of 96 million tonnes at 0.57% copper and inferred mineral resources of 31 million tonnes at 0.71% copper, with the potential to be mined earlier in the mine life. The Copper World deposits contain higher grade mineralization that often starts at or very near surface.

The Mason deposit, acquired in late 2018, is one of the largest undeveloped copper resources in the Americas. It is similar in scale to Constancia and Rosemont.

In July 2019, the US District Court for Arizona issued a ruling that vacated the Final Record of Decision (FROD) issued by the US Forest Service. As a result, our ability to move ahead with building Rosemont is suspended for the time being. Simply put, the judge ruled that the decision to issue the FROD was based on an incorrect interpretation of mining claims.

We have appealed the ruling. Hudbay believes that the Court misinterpreted federal mining laws and Forest Service regulations as they apply to Rosemont.

Fact

The Copper World project consists of seven mineral deposits with the majority located on private mining claims adjacent to Rosemont. A significant amount of the resources are high-grade and near surface.

Green Economy

From solar panels to electric vehicles—copper is a key element in de-carbonization efforts and the shift to renewable energy sources. Hudbay will support America's transition to a cleaner future, by providing the copper we need to build the innovative products and technologies that will power our new sustainable future.

Environment

Modern mining begins with the end in mind. For Copper World, that means planning for the closure and reclamation of the land will be one of the first steps in developing the mine.

Hudbay submitted and received approval from the Arizona State Mine Inspector for our initial reclamation plan for Copper World. We expect to advance other state permits in 2022.

People

As the next chapter of Arizona mining, the Copper World and Rosemont projects will stimulate billions in new economic activity statewide. Locally, Hudbay will create thousands of new direct and indirect, high-paying jobs for Arizonans and ensure the future of Arizona mining remains strong.

Reserves and resources - Rosemont

Rosemont Project


Mineral Reserve and Resource Estimates - January 1, 20221,2,3,4,5
Tonnes Cu
(%)
Mo
(g/t)
Ag
(g/t)
Proven 426,100,000 0.48 120 4.96
Probable 111,000,000 0.31 100 3.09
Total proven and probable 537,100,000 0.45 116 4.57
Measured 161,300,000 0.38 90 2.72
Indicated 374,900,000 0.25 110 2.60
Total Measured & Indicated 536,200,000 0.29 104 2.64
Inferred 62,300,000 0.30 100 1.58

Note: totals may not add up correctly due to rounding.
1Mineral resources are exclusive of mineral reserves and do not have demonstrated economic viability.
2 Mineral resources do not include factors for mining recovery or dilution.
3 Blocks were classified as Proven or Probable in accordance with CIM Definition Standards 2014.
4 Mineral reserves were estimated using metal prices of $3.15 per pound copper, $11.00 per pound molybdenum and $18.00 per ounce silver. 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. An NSR cut-off value of $6.60 per tonne was assumed, based on process recoveries and total processing and general and administrative operating costs.
5 Mineral resources are constrained within a computer generated pit using the Lerchs-Grossman algorithm and were estimated 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 and total processing and general and administrative operating costs of $6.10 per tonne for oxide, mixed and sulfide material.


Reserves and resources - Copper World

Copper World Project


Mineral Resource Estimates1,2,3,4,5,6
Potential Processing Method Category Tonnes Cu
(%)
CuSS
(%)
Mo
(g/t)
Ag
(g/t)
Flotation Indicated 180,000,000 0.37 0.07 136 2.7
Inferred 91,000,000 0.36 0.05 129 3.8
Leach Indicated 92,000,000 0.34 0.27 - -
Inferred 51,000,000 0.35 0.27 - -
Total Indicated 272,000,000 0.36 0.14 90 1.8
Inferred 142,000,000 0.36 0.13 83 2.4

Note: totals may not add up correctly due to rounding.
1CIM definitions were followed for the estimation of mineral resources. Mineral resources that are not mineral reserves do not have demonstrated economic viability.
2 Mineral resources are reported within an economic envelope defined by a pit shell optimization algorithm and assuming a selective mining unit of 50x50x50 feet. This pit shell is defined by a revenue factor of 1.0 assuming operating costs adjusted and updated from the 2017 Rosemont Feasibility Study.
3Mineral resource estimates were reported using a cut-off of 0.1% Cu and were separated by potential processing method into flotation and leach if they respectively had a CuSS/Cu ratio below or above a threshold of 50%.
4 Metal recovery estimates assume that this mineralization would be processed at a combination of facilities, including copper and molybdenum flotation and heap and/or run-of-mine leach pads followed by solvent extraction and electrowinning.
5 CuSS represents the copper grade in oxides.
6 Specific gravity measurements were estimated from core box weights validated by industry standard laboratory measurements.

Copper World Project


High Grade Mineral Resource Estimates 1,2,3
Potential Processing Method Category Tonnes CuT
(%)
CuSS
(%)
Mo
(%)
Ag
(g/t)
Flotation Indicated 48,000,000 0.68 0.14 125 4.0
Inferred 13,000,000 0.78 0.18 136 3.6
Leach Indicated 48,000,000 0.46 0.37 68 4.2
Inferred 18,000,000 0.66 0.49 50 3.7
Total Indicated 96,000,000 0.57 0.26 97 4.1
Inferred 31,000,000 0.71 0.36 86 3.7

1As at December 1, 2021
2 Mineral resource estimates in this Table 2 are defined by a revenue factor of 0.36. A lower revenue factor typically indicates the optimal mining sequence and highlights mineralization that has the potential to be mined earlier in the mine life in order to maximize the value of the operation.
3The higher grade mineral resources shown in Table 2 above are included in the global mineral resource estimate presented in Table 1.

Reserves and resources - Mason

Mineral Resource Estimates - January 1, 20221,2,3,4,5 Tonnes Cu Grade(%) Mo Grade(g/t) Au Grade(g/t) Ag Grade(g/t)
Measured 1,417,000,000 0.29 59 0.031 0.66
Indicated 801,000,000 0.30 80 0.025 0.57
Total Measured and Indicated 2,219,000,000 0.29 67 0.029 0.63
Inferred 237,000,000 0.24 78 0.033 0.73

Note: totals may not add up correctly due to rounding.
1 Mineral resource estimates that are not mineral reserves do not have demonstrated economic viability.
2 Mineral resource estimates do not include factors for mining recovery or dilution.
3 Metal prices of $3.10 per pound copper, $11.00 per pound molybdenum, $1,500 per ounce gold, and $18.00 per ounce silver were used to estimate mineral resources.
4 Mineral resources are estimated using a minimum NSR cut-off of $6.25 per tonne.
5 Mineral resources are based on resource pit designs containing measured, indicated, and inferred mineral resources.