Section 06 PRODUCTS OF THE CHEMICAL OR ALLIED INDUSTRIES 28 INORGANIC CHEMICALS; ORGANIC OR INORGANIC COMPOUNDS OF PRECIOUS METAL, OFRARE-EARTH METALS, OF RADIOACTIVE ELEMENTS OR OF ISOTOPES 28 05 ALKALI, OR ALKILINE-EARTH METALS; RARE-EARTH METALS, SCANDIUM AND YTTRIUM, 28 05 12 CALCIUM Commodity Code Description 28 05 12 00 CALCIUM