Abstract: A method of treating ferromanganese alloys in a suitable reactor wherein the feed material is heated by a transferred-arc thermal plasma and is fed directly to the reactor bath. Accordingly, the molten bath defines a reaction zone and at least a part of the molten bath defines a lower electrode surface for the arc. In particular, ferromanganese alloy fines may be remelted to form a physically more massive form of the alloy and additionally may be refined by the addition of suitable metal oxides to yield a product wherein the content of at least silicon or carbon is lowered.