Section 06 Products of the chemical or allied industries 28 Inorganic chemicals; organic or inorganic compounds of precious metals, of rare - earth metals, of radioactive elements or isotopes 28 44 Radioactive elements and isotopes and compounds other than those of Subheading 2844.. Commodity Code Description 28 44 10 Natural uranium and its compounds; alloys, dispersions (including cerments), ceramic ... 28 44 20 Uranium enriched in U 235 and its compounds; plutonium and its compounds alloys ........ 28 44 30 Uranium depleted in U 235 and its compounds; thorium and its compounds; alloys, ..... 28 44 40 Radioactive elements and isotopes and compounds other than those of subheading 2844.10.. 28 44 41 Tritium and its compounds; alloys, dispersions (including cermets), ceramic products 28 44 42 Actinium-225, actinium-227, califorminium-253, curium-240, curium-241, curium-242, cu 28 44 43 Other radio active elements and isotopes and compounds; other alloys, dispersions (in 28 44 44 Radioactive residues 28 44 50 Spent (irradiated) fuel elements (cartridges) of nuclear reactors