IGO has been undertaking a strategic review in an attempt to revaluate its resources.
The American Exploration & Mining Association was joined by a coalition in filing a challenge last Friday in the Wyoming district court.
There are some 10,000 mining claims in Grassy Narrows’s interim area of interest for over more than 2,850 sq. km in the province’s far northwest.
Portugal already has the largest copper mine in the European Union, operated by Lundin Mining.
