19 construction materials except for those made of metal, namely, natural stones, artificial stones, roofing cement, portland cement, non-agricultural lime, mortars, gypsum tiles, gravel, pipes made of sandstone or cement, plastic mounting and transport plates for floor heaters, lightweight concrete for use in joists, concrete with an addition of granulate-type foamed polystyrene for use in constructing patios, mortar mixtures, and prefabricated concrete components for use in erecting columns; road construction materials, namely, asphalt, bitumen and pitch; manufactured housing, namely, mobile homes and stone monuments