| 2615 | | Niobium (columbium), tantalum, vanadium or zirconium ores and concentrates: | | | | |
| 2615.90.30 | 00 | Synthetic tantalum-niobium (columbium) concentrates | kg | Free | | 30% |
| 2615.90.60 | 30 | Niobium (columbium) ores and concentrates | kg | | | |
| 2825.90.15 | 00 | Niobium oxide | kg | 3.7% | Free (A*,AU,BH, CA,CL,E,IL,J,JO, MA,MX,P,SG) | 25% |
| 7202.93 | | Ferroniobium: | | | | |
| 8112 | | Beryllium, chromium, germanium, vanadium, gallium, hafnium, indium, niobium (columbium), rhenium and thallium, and articles of these metals, including waste and scrap: | | | | |
| 8112.92.40 | 00 | Niobium (columbium) | kg | 4.9% | Free (A+,AU,BH, CA, CL,D,E,IL,J, JO,MA,MX, P,SG) | 25% |
Harmonized Tariff Schedule of the United States inquiry: 534
