| 2843 |  | Colloidal precious metals; inorganic or organic compounds of precious metals, whether or not chemically defined; amalgams of precious metals: |  |  |  |  | 
| 2844 |  | Radioactive chemical elements and radioactive isotopes (including the fissile or fertile chemical elements and isotopes) and their compounds; mixtures and residues containing these products: |  |  |  |  | 
| 2844.10.20 | 25 | Hexafluoride | kg |  |  |  | 
| 2844.20.00 |  | Uranium enriched in U235 and its compounds; plutonium and its compounds; alloys, dispersions (including cermets), ceramic products and mixtures containing uranium enriched in U235, plutonium or compounds of these products |  | Free |  | Free | 
| 2844.20.00 | 20 | Fluorides | kg |  |  |  | 
| 2844.30 |  | Uranium depleted in U235 and its compounds; thorium and its compounds; alloys, dispersions (including cermets), ceramic products and mixtures containing uranium depleted in U235, thorium, or compounds of these products: |  |  |  |  | 
| 2844.30.20 | 20 | Fluorides | kg |  |  |  | 
| 2844.40.00 |  | Radioactive elements and isotopes and com- pounds other than those of subheadings 2844.10, 2844.20, and 2844.30; alloys, dis- persions (including cermets), ceramic products and mixtures containing these elements, isotopes or compounds; radioactive residues |  | Free |  | Free | 
| 2844.50.00 | 00 | Spent (irradiated) fuel elements (cartridges) of nuclear reactors | kg | Free |  | Free | 
| 2845 |  | Isotopes other than those of heading 2844; com- pounds, inorganic or organic, of such isotopes, whether or not chemically defined: |  |  |  |  | 
| 2846 |  | Compounds, inorganic or organic, of rare-earth metals, of yttrium or of scandium, or of mixtures of these metals: |  |  |  |  | 
| 2846.90.20 |  | Mixtures of rare-earth oxides or of rare-earth chlorides |  | Free |  | 25% | 
| 2847.00.00 | 00 | Hydrogen peroxide, whether or not solidified with urea | kg | 3.7% | Free (A,AU,BH, CA,CL,E,IL,J,JO, MA,MX,P,SG) | 25% | 
| 2848.00 |  | Phosphides, whether or not chemically defined, excluding ferrophosphorus: |  |  |  |  | 
| 2848.00.10 | 00 | Of copper (phosphor copper), containing more than 15 percent by weight of phosphorus | kg | 2.6% | Free (A,AU,BH, CA,CL,E,IL,J,JO, MA,MX,P,SG) | 32.5% | 
| 2848.00.90 | 00 | Of other metals or of nonmetals | kg | Free |  | 25% | 
| 2849 |  | Carbides, whether or not chemically defined: |  |  |  |  | 
| 2849.10.00 | 00 | Of calcium | kg | 1.8% | Free (A*,AU,BH, CA,CL,E,IL,J,JO, MA,MX,P,SG) | 10% | 
| 2849.20 |  | Of silicon: |  |  |  |  | 
| 2849.20.20 | 00 | In grains, or ground, pulverized or refined | kg | 0.5% | Free (A,AU,BH, CA,CL,E,IL,J,JO, MA,MX,P,SG) | 1.6% | 
| 2849.90.10 | 00 | Of boron | kg | 3.7% | Free (A,AU,BH, CA,CL,E,IL,J,JO, MA,MX,P,SG) | 25% | 
| 2849.90.20 | 00 | Of chromium | kg | 4.2% | Free (A,AU,BH, CA,CL,E,IL,J,JO, MA,MX,P,SG) | 25% | 
| 2849.90.30 | 00 | Of tungsten | kg W kg | 5.5% | Free (A+,AU,BH, CA,CL,D,E,IL,J, JO,MA,MX, P,SG) | 55.5% | 
| 2850.00 |  | Hydrides, nitrides, azides, silicides and borides, whether or not chemically defined, other than compounds which are also carbides of heading 2849: |  |  |  |  | 
| 2850.00.05 | 00 | Of calcium | kg | Free |  | 25% |