About The Project

The Twin Metals Minnesota (TMM) Project is focused on designing, constructing and operating an underground copper, nickel, platinum, palladium, gold and silver mining project. Located approximately nine miles southeast of the city of Ely, Minnesota, and 11 miles northeast of the city of Babbitt, Minnesota, the TMM Project targets the valuable minerals within the Maturi deposit, part of the Duluth Complex geologic formation.

Pending a resolution of its federal mineral rights, TMM expects to submit a formal mine plan proposal in the next two years, initiating a rigorous and thorough environmental review by multiple state and federal agencies as required by law.


  • January 2010: After Duluth Metals Limited identified strategic metals deposits, the company formed a partnership with Antofagasta plc, one of the top 10 global copper producers, and together they founded Twin Metals Minnesota LLC.
  • February 2011: Twin Metals Minnesota acquired Franconia Minerals Corporation, effectively doubling Twin Metals Minnesota’s mineral and land assets, providing the opportunity for greater efficiency, more jobs and maximum environmental protection for the project.
  • January 2015: Antofagasta plc purchased Duluth Metals Limited in a friendly acquisition, placing the TMM Project under Antofagasta’s unilateral control.
  • Today: Twin Metals Minnesota is a wholly owned subsidiary of Antofagasta plc continuing to focus on designing, constructing and operating an underground strategic metals mine in northeast Minnesota.

TMM continues advancing compact and efficient designs for a project that will process approximately 20,000 tons of mineralized ore per day. Underground mining operations allow for maximizing underground storage of waste rock and tailings, minimizing the impacts of mining activities. Ongoing studies are focused on detailed engineering, economic and site-specific environmental studies of the project details, facilities locations and more. These studies will culminate in the formal mine plan of operation (MPO). Pending a resolution of its federal mineral rights, TMM expects to submit the MPO in the next two years.

Twin Metals has been conducting environmental studies for more than five years, and these efforts will be ongoing. Environmental information will be used to evaluate potential project impacts during the formal Environmental Impact Statement (EIS) process that will be conducted by state and federal agencies. Today’s environmental regulations tightly restrict how mines are designed and operated. State and federal agencies require strict adherence to regulations surrounding key environmental issues, including surface water and groundwater quality, threatened and endangered species, air quality, plant life, wetlands and more. Environmental requirements must be met or exceeded, or the TMM Project will not be authorized to move forward.