FOR IMMEDIATE RELEASE
October 7, 2025
South32 has released a new animated video that provides viewers with a deep dive look into the design and operation of its zinc processing facility at Hermosa, following zinc’s journey from underground in the Patagonia Mountains to final shipment as a lead-silver concentrate and zinc concentrate.
“Few mining projects today allow us to start with a blank sheet of paper,” said Pat Risner, South32 Hermosa President. “That’s what makes Hermosa unique. We’re able to intentionally design and develop a processing facility with equipment representing the latest in technological advancements and energy efficiency.”
A Facility Built with Sustainability in Mind
Unlike traditional processing facilities, Hermosa’s is designed from the ground up to use less energy, water, and chemicals—minimizing impact while maximizing efficiency. Key features include:
- Sealed transport: Instead of leaving ore in open piles, it will be stored in large silos, moved on covered conveyor belts, and into sealed containers that will be shipped from Hermosa. This fully enclosed approach eliminates the potential for dust or material exposure into the environment.
- Smarter use of energy and space: The facility will rely on efficient equipment that conserves electricity while delivering the same results. Its flotation cells use about 30% less power and occupy 40% less space than conventional models, requiring less concrete and structural steel on an already compact footprint. Additional innovations, including vertical tower mills used as a secondary grinding mill, and a shared concentrate filter, further reduce energy demand and optimize mineral separation.
- Responsible water use: After the minerals are separated, about 90% of the water pressed out of the processed ore is recovered and reused in the processing plant making water consumption much lower than most mining operations.
- Tailings and backfill: The remaining material after our minerals have been recovered, known as ‘tailings’ are managed two ways. A portion of that processed material will be mixed into cement and pumped back underground to fill mined-out areas, which will reduce surface impact and support ground stability. Tailings destined for the dry stack tailings storage facility are dewatered using large filter presses, where about 90% of moisture content is removed. The removed water is recycled to the processing plant. The dewatered tailings are compacted and placed on Hermosa’s lined dry-stack tailings storage facility.
- Built for the future: Because ore quality can change from day to day, the plant is designed to adapt to changes in ore composition—feed rates, concentrations, and qualities—without affecting safety or the quality of the final product.
“This facility represents more than simply processing zinc, it’s part of our commitment to produce critical minerals in a way that minimizes impacts to our environment, supports the local economy, and builds a stronger future for the region,” said Risner.
Zinc is a critical mineral used to galvanize steel, making it essential for infrastructure like roads, bridges, and power transmission. Hermosa has the potential to be one of the world’s largest zinc producers, providing the critical minerals needed for the energy transition responsibly and locally.
By processing its ore on-site, Hermosa will generate value that flows back into Santa Cruz County through jobs, community investment, and long-term regional growth.
To view the video and learn more about the zinc processing facility, click here.
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About South32 Hermosa
Located in a historic mining district in the Patagonia Mountains of Southern Arizona, Hermosa is currently the only advanced mine development project in the United States that could produce two federally designated critical minerals — manganese and zinc — both of which are essential minerals for powering the nation’s energy future. Learn more at www.south32hermosa.com.
Hermosa is a polymetallic development comprised of a zinc-lead-silver sulfide deposit, a battery-grade manganese deposit and an extensive, highly prospective land package with the potential for further polymetallic and copper mineralization.
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