Sand, gravel, crushed stone, asphalt, bitumen, cement, gypsum, plaster, concrete, marble blocks for construction, included in this class; 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, included in this class; non-metallic buildings, non-metallic building materials, poles not of metal for power lines, barriers not of metal; natural and syntheti...