Section 06 PRODUCTS OF THE CHEMICAL OR ALLIED INDUSTRIES 28 Inorganic chemicals; organic or inorganic compounds of precious metals , of rare 28 36 Carbonates; peroxocarbonates (percarbonates); commercial ammonium carbonate cont Commodity Code Description 28 36 20 28 36 30 28 36 40 28 36 50 28 36 60 28 36 91 28 36 92 28 36 99