The metal extracted industrially by the Hall–Héroult electrolytic process is

1. Reactive metals whose oxides cannot be reduced by carbon are obtained by electrolysis. 2. In the **Hall–Héroult process**, molten alumina dissolved in cryolite is electrolysed to give aluminium at the cathode. 3. Copper and nickel are refined electrolytically but are not extracted by Hall–Héroult; zinc is obtained by carbon reduction. _Source: Samacheer Kalvi Class 12 Chemistry Vol.1, Unit 1 'Metallurgy', §1.5.1_