Tantalum Metal Powder, 1. Ta: 99.95%min. 2. O: 900ppm.max. 3. Size: 3--5um, or 5--8um. Tantalum Powder, Specification as follows:Ta>99.95%, O<900ppm, H<10ppm, C<30ppm, N<25ppm, Si<15ppm, Ti<10ppm,Mo<8ppm, W<20ppm, Mn<5ppm, Ni<15ppm, Fe<15ppm, Mg<10ppm, Cr<15ppm, Nb<40ppm.