The project, which would become the European Union's only open-cast uranium mine if given the go-ahead, has faced local opposition since it was proposed.
Hydro, which is not interested in acquiring aluminium plants that use coal-fired power, was hoping the deal would be part of efforts to make its output as green as possible.
The proposed tax, to be applied on the nominal value of extracted metals, would affect copper miners that produce more than 12,000 tonnes of the metal and those extracting 50,000 tonnes of lithium a year.
The world’s top diamond producer by value has led industry efforts to both verify the authenticity of diamonds and ensure they are not from conflict zones where gems may be used to finance violence.
Company won’t have to cut output at its central BC-based copper-gold mine, at least for now, as it has been granted approval to use certain short-term water sources.