1.Nb2O5>99.99% 2.Ti<0.0001%,W<0.0003%,Mo<0.0002%,Cr<0.0003%,Mn<0.0002%, Fe<0.0005%,Ni<0.0003%,Cu<0.0003%,Al<0.0003%,Si<0.001% niobium pentoxide, white powder, quality is ok.specification: Nb2O5>99.99%, Ti<0.0001%, W<0.0003%, Mo<0.0002%, Cr<0.0003%,Mn<0.0002%, Fe<0.0005%, Ni<0.0003%, Cu<0.0003%, Al<0.0003%,Si<0.0010%, F<0.0050%