Carbides of aluminium, of chromium, of molybdenum, of vanadium, of tantalum, and of titanium, whether or not chemically defined
Carbides of boron, whether or not chemically defined
Carbides of tungsten, whether or not chemically defined
Carbides, whether or not chemically defined (excl. of calcium, silicon, boron, tungsten, aluminium, chromium, molybdenum, vanadium, tantalum, titanium, and inorganic or organic compounds of mercury whether or not chemically defined)