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Production of niobium and/or tantalum powders comprises reducing corresponding niobium and/or tantalum oxides using alkaline earth metals and/or rare earth metals. Reduction is carried out in two stages at controlled temperature. The first reaction step is carried out up to an average composition (Nb, Ta)Ox (where, x = 0.5-1.5), and before the second step the reduction product from the first step is liberated by washing with mineral acids of alkaline earth oxides, rare earth metal oxides and excess alkaline earth metal and/or rare earth metal. An Independent claim is also included for a niobium powder agglomerate having a primary grain size of 0.1-1 microns diameter and an agglomerate diameter distribution of 100-300 microns.