… the pearl oyster and the pearl mussel). Pearls have a shiny surface and consist essentially of layers of calcium … (conchiolin). The layers of carbonate cause optical interference and diffraction which produce the …
… manufacture of special cements, for coating non‑metallic surfaces as a basis for electroplating, etc. The flakes are … colouring matter by blowing them, e.g., on to a varnished surface to which they adhere. The heading does not cover : …
… of this heading may have been subjected to the following surface treatments : (1) Descaling, pickling, scraping and … (steel “ twists ”); and (3) Bars and rods having a single perforation to facilitate transportation. The heading, …
… operation, or capable of flight which is programmed to be performed without the intervention by an operator . Although … or amusement purposes, and that are not designed to perform utilitarian functions. They can be distinguished , …
… the “weld bead”, which is clearly visible on the external surface of the finished tube. Subheading 7305.12 This … welding there is no raised bead of metal on the external surface of the finished tube. …
… turning centres) of this heading are machines used for surface‑working metal by cutting away or otherwise removing … movements of the machine-tool, tool or workpiece must be performed according to pre-programmed instructions. The …
… salts of perchloric acid (HClO 4 ) (heading 28.11). These powerful oxidising agents are used in pyrotechnics and in … Used in the chemical industry as an oxidising agent more powerful than chlorates. (4) Other perchlorates . These …
