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Concrete is a mixture of materials, the variability of which can influence the colour of the finished concrete. However, if the same sources of materials are maintained throughout a contract, these inherent variations should not alter the final colour significantly. A mottled surface is, to some extent, indicative of a well compacted concrete. Some variation in colour, even with nominally the same concrete, is impossible to avoid. Concrete will never be a monotone block colour as would be expected, for example, from a painted surface.

A brushed finish is obtained by pulling a brush over the surface of the fresh concrete, after the surface has been levelled. The type of finish obtained will depend upon the coarseness of the brush bristles and the length and shape of the tufts. Coarse texture is given by stiff-bristled brooms, softer bristles giving medium and light textures. Brushes can have plastic bristles or steel tines of varying gauge and density. Normal manual sweeping brooms produce an unsatisfactory texture for finishing concrete surfaces and should not be used

A tamped finish for unformed surfaces is produced by raising and lowering the compacting beam in its final pass to produce a surface with ridges at a fairly regular spacing of 20 to 30mm and up to 5mm high. Generally the grooves should be in the direction of drainage falls and on ramps (for example in car parks) should follow a chevron pattern. If the tamped finish is too heavy, it will impede drainage and lead to contaminants being trapped in the bottom of the grooves.

It should be noted that it is difficult to maintain an even distribution of ridges. In addition there will be variations from pour to pour, due to