The miner initially aimed to have a PFS for Taylor completed in the September quarter of this year.

South32 said study work to date supported a potential unconstrained development of Taylor, including its integration with the Clark deposit, for which a scoping study was under way.

“All options under consideration have different cost, permitting and schedule implications,” the diversified mining company said.

The Taylor deposit hosts some 155-million tonnes, grading 3.39% zinc, 3.67% lead, 69 g/t silver for some 5.3-million tonnes of zinc, 5.7-million tonnes of lead and 344-million tonnes of silver, while the Clark deposit has a resource of 55-million tonnes, grading 2.31% zinc, 9.08% manganese and 78 g/t silver for the Clark deposit.

South32 acquired Hermosa as part of the $1.3-billion acquisition of TSX-listed Arizona Mining, in 2018.