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 16 Hydroxide and peroxide of magnesium; oxides, hydroxides and peroxides, of strontium or barium. 28 16 40 Oxide, hydroxides, and peroxides of strontium or barium Commodity Code Description 28 16 40 00 Oxide, hydroxides, and peroxides of strontium or barium