Details：
Tantalum metal powder: Ta ≥ 99.9%
Tantalum pentoxide: Ta2O5≥ 99.9～99.99%
Tantalum pipe, silk, board and stick: Ta≥99.9%
Niobium stick: Nb≥99～99.9%
Niobium pentoxide: Nb2O5≥99%~99.99%
Niobium hydroxide: Nb(OH)2≥99.99%