… Bricks, blocks, tiles and other ceramic goods of siliceous fossil …
Explanatory notes
… or of silica obtained by the incineration of certain vegetable products (e.g., rice boll ash). These materials … compounds. Refractory materials are used mainly to line blast furnaces, coke ovens, petroleum cracking plants, … the appropriate heading of sub-Chapter II. 69.01 - Bricks, blocks, tiles and other ceramic goods of siliceous fossil …