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Hermosa has the potential to become a globally significant producer of metals critical to a low-carbon future.

Hermosa Project

1860 E River Road, Suite 200
Tucson, Arizona 85718
United States of America

More information on the Hermosa Project can be found on its local website:


Key statistics


South32 share


Invested into the community in FY22

Our development option

Located in the Patagonia Mountains, about 80 kilometres south-east of Tucson, Arizona, Hermosa comprises the zinc-lead-silver Taylor sulphide deposit (Taylor Deposit), and the zinc-manganese-silver Clark oxide deposit (Clark Deposit). In addition to the Taylor and Clark deposits, Hermosa has a highly prospective broader land package, which includes the copper-lead-zinc-silver Peake exploration target, as well as the Flux prospect.

Strongly complementing our existing portfolio, Hermosa provides the opportunity to leverage the underground mining and processing methods we've used at our Cannington operation in Queensland, Australia.

Our work at Hermosa is helping to fulfill our strategy by reshaping our portfolio to produce the metals that are critical for a low-carbon future.

Next generation mining

In January 2022, we reached an important milestone for our Hermosa project, located in Arizona, USA, with the publication of results from the pre-feasibility study for the Taylor Deposit – the first development option at the project.

The results demonstrate that Taylor has the potential to be a sustainable, highly productive zinc-lead-silver underground mine with a conventional processing plant.

It is being designed as our first ‘next generation mine’, using automation and technology to minimise our impact on the environment and in line with our goal of achieving net zero operational carbon emissions by 2050. Learn more about the PFS here

We expect to complete the feasibility study for our Taylor deposit in the second half of CY23.

Hermosa also includes the spatially-linked zinc-manganese-silver Clark Deposit.

Our work to date has confirmed the potential for the Clark Deposit to produce battery-grade manganese for the growing North American electric vehicle supply chain, with zinc and silver co-products. We are collecting bulk samples at Clark ahead of pilot plant production of battery grade Manganese from mid-calendar year 2023 to support ongoing customer engagements. 

We’re also unlocking value through the exploration of our regional scale land package. We have identified a highly prospective corridor which will be prioritised for future drilling.

Our commodities


Unearthing beneficial uses of excess groundwater at the Hermosa project

We recognise the value of working with experts to help achieve our sustainability commitment across our operations and projects. At the Hermosa project, safe and sustainable underground exploration will require moving groundwater away from the orebodies. This will be accomplished by pumping groundwater away from the orebodies and returning it to the neighboring environment after treating it to the highest applicable water quality standards. Watch the video to learn more.

  • Pat Risner

    Hermosa President

    Pat studied Mining Engineering at the University of Missouri and came to South32 from BHP, where he held the position of Group Health, Safety and Environment Officer
    He is an experienced mining operator, having worked in technical, planning and operational roles in both the United States and Australia. With strong leadership experience in mining health, safety, and environment, he is regarded as an industry expert in complex project planning and development.


1860 E River Road, Suite 200, Tucson, Arizona 85718, United States of America