crushed abrasives, namely, basalt, granite, aluminia, furnace slag or igneous rock for forming abrasion-resistant linings or coatings for tiles, pipes, conduits, chutes, bunkers and bins which convey or hold abrasive mixtures

Wear-resistant, corrosion-resistant, abrasion-resistant, adhesion-resistant, impact-resistant, rot-resistant, acid-resistant, moisture-resistant, heat-resistant and slide-promoting non-metal building materials, in particular non-metal building boards, moulded and formed parts in the nature of non-metal plates, panels, plankings, slabs, inserts, and castings, for conduits, chutes, channels, conveyors, containers, bunkers, silos, mixers and pipes, hollow parts in the nature of tubes, plankings,...