Siltstone and sandstone products provided for in this class, including bricks, building materials, cladding, columns for buildings and displaying artworks, crash barriers, floor tiles, grave or tomb enclosures, gravel, gravestone slabs, gravestones, houses, letter boxes, lintels, mantelpieces, memorial plaques, monuments, mosaics for building, paving blocks, paving slabs, pebbles, pergolas, planters, retaining walls, road coating materials, road base, road paving, rubble, shingles, signs, slag, staircases, steps, works of stonemasonry, swimming pools, ponds and basins, and works of art