2319 Manufacture and processing of other glass, including technical glassware

231911 Glass in the mass, in balls (except microspheres), rods or tubes, unworked 231912 Paving blocks, bricks, tiles and other articles of pressed or moulded glass/ leaded lights and the like/ multicellular or foam glass in blocks, plates or similar forms 231921 Glass envelopes, open, and glass parts thereof, for electric lamps, cathode-ray tubes or the like 231922 Glasses for clocks, watches or spectacles, not optically worked/ hollow spheres and their segments, for the manufacture of such glasses 231923 Laboratory, hygienic or pharmaceutical glassware/ ampoules of glass 231924 Glass parts for lamps and lighting fittings, illuminated signs, name-plates and the like 231925 Electrical insulators of glass 231926 Articles of glass n.e.c.