… Hydrides, nitrides, azides, silicides and borides, whether or not chemically defined, other than compounds which are also carbides of heading 28.49. …
Explanatory notes
… 28.50 ‑ Hydrides, nitrides, azides, silicides and borides, whether or not chemically defined, other than compounds which are also carbides of heading 28.49. The four groups of … (hydrolith) obtained by direct combination of its elements; white masses with a crystalline fracture, decomposing in the …