19 Beams, not of metal; concrete; joists, not of metal; geotextiles, in the nature of fabrics for use in civil engineering; clay flooring; granite; doors, not of metal; prefabricated houses, not of metal; limestone; works of stonemasonry, namely, stone sculptures; works of art of stone, concrete or marble; stone; artificial stone; building stone; cornices, not of metal; pillars, not of metal, for building; cement posts; brackets, not of metal, for building; transportable buildings, not of metal; roofing, not of metal; staircases, not of metal; reinforcing materials, not of metal, for building; bituminous products for building, namely, bituminous roof coatings; pitch; building materials, not of metal, namely, floor boards; refractory construction materials, not of metal; wall claddings, not of metal, for building; laths, not of metal; wall linings, not of metal, for building; windows, not of metal; shuttering, in the nature of roll shutters, not of metal, for concrete enclosures; props, not of metal; wainscotting, not of metal; building panels, not of metal; partitions, for building, not of metal; platforms, prefabricated, not of metal; wall tiles, not of metal; tiles, not of metal, for building; cement slabs; paving blocks, not of metal; fireproof cement coatings; linings, not of metal, for building; mortar for building; posts, not of metal; non-metal hips for roofing; cement; pantiles, not of metal; concrete building elements, namely, concrete slabs