US-based developer Electric Metals has unveiled an upgraded mineral resource estimate for its Emily manganese project, solidifying the Minnesota project as the continent’s “highest-grade manganese resource”.

At a 10% cutoff grade, Emily’s indicated resources increased by 20.9% to 6.2-million tons, with a grade of 19.27% manganese. Inferred resources surged by 596.5% to 4.9-million tons, with a grade of 17.5%.

Electric Metals CEO Brian Savage underscores the quality of the Emily deposit, saying numerous core samples exceed 50% manganese – a grade unparalled in North America and much of the world.

The company’s focus is to convert Emily’s resources into high-grade mineable reserves, and to advance the metallurgical testing to refine and optimise the flow sheet for the production of high-value, high-grade manganese chemicals and products.

Electric will be undertaking studies to determine potential sites for a high-purity manganese sulphate monohydrate plant and to perform a scoping or prefeasibility level study for the plant.

With no manganese mine supply in North America, governments and regulators are pushing to build a domestic US supply chain. Manganese is on the Department of Commerce’s list of minerals critical to the US economy.

Shares in Electric Metals jumped 12% on the TSX on Monday to C$0.14 apiece, following the resource estimate announcement.