The copper and nickel contained in the rocks southeast of Ely has already been described as a "monster deposit" by the mining industry. When Twin Metals issues a new estimate of just how precious those metals are, the figure seems likely to exceed its previous number of $100 billion. MPR watched as the company tested a rock sample from one of more than 400 holes it has drilled.
There's no guarantee the minerals will ever be mined, though. Some of the most serious concerns involve the sulfide that's also contained in those rocks. That sulfide creates sulfuric acid when it's exposed to air or water. Managing the acid is one of the issues that will be part of the environmental permitting process, which is still in its early stages.