19 Sand, gravel, crushed stone, asphalt, bitumen, cement, gypsum for use as building materials, plaster, concrete, marble blocks for construction; building materials as finished products made of concrete, gypsum, clay, potters' clay, stone, marble, wood, plastics and synthetic materials for building, construction, road construction purposes, namely, non-metal floor tiles, non-metal soffits, composite panels composed primarily of nonmetal materials; non-metallic transportable buildings; non-metallic building materials being non-metal floor tiles, non-metal soffits, composite panels composed primarily of nonmetal materials, poles not of metal for power lines, barriers not of metal in the nature of crash barriers, noise barriers made of wood, crowd control barriers; natural and synthetic coatings in the form of panels and sheets, being building materials, namely, facing sheets of plywood, common sheet glass for building; bitumen cardboard coatings for roofing; bitumen coating for roofing; doors and windows of wood and synthetic non-metal materials; traffic signs not of metal, non-luminous and non-mechanical, for roads; monuments and statuettes of stone, concrete and marble; building glass; structures, namely, prefabricated swimming pools not of metal; aquarium sand