2850 Hydrides, Nitrides, Azides, Silicides and Borides, Whether or not Chemically Defined (Excl. Compounds Which are Also Carbides of Heading 2849) [01/01/1988-31/12/1991: Hydrides, Nitrides, Azides, Silicides and Borides, Whether or not Chemically Defined]

2850 (01/1988-..) Hydrides, Nitrides, Azides, Silicides and Borides, Whether or not Chemically Defined (Excl. Compounds Which are Also Carbides of Heading 2849) [01/01/1988-31/12/1991: Hydrides, Nitrides, Azides, Silicides and Borides, Whether or not Chemically Defined] 28500010 (01/1988-12/1997) Hydrides, Whether or not Chemically Defined, (Excl. Compounds Which are Also Carbides of Heading 2849) 28500020 (01/2012-..) Hydrides and Nitrides, Whether or not Chemically Defined (Excl. Compounds Which are Also Carbides of Heading 2849, and Inorganic or Organic Compounds of Mercury) 28500030 (01/1988-12/1997) Nitrides, Whether or not Chemically Defined, (Excl. Compounds Which are Also Carbides of Heading 2849) 28500050 (01/1988-12/2008) Azides, Whether or not Chemically Defined (Excl. Compounds Which are Also Carbides of Heading 2849) 28500060 (01/2012-..) Azides, Silicides, Whether or not Chemically Defined (Excl. Compounds Which are Also Carbides of Heading 2849, and Inorganic or Organic Compounds of Mercury) 28500070 (01/1988-12/2008) Silicides, Whether or not Chemically Defined (Excl. Compounds Which are Also Carbides of Heading 2849) 28500090 (01/2012-..) Borides, Whether or not Chemically Defined (Excl. Compounds Which are Also Carbides of Heading 2849, and Inorganic or Organic Compounds of Mercury)