New Floors vs Retrofit Polished Concrete Floors
If you think of polishing concrete much like sanding wood you can compare the aggregate look to the wood grain. For this reason you have the option to customise the look of your floor if it is a new floor vs if you are posishing an existing floor. With existing floors you are limited to the existing aggregate that is in the concrete. As concrete is polished the surface is gradually ground down to the desired shine and smoothness finish. The existing aggregate will become the feature of the new surface. There is an option to apply a 'topping slab' to an existing slab if a particular aggregate finish is desired. The minimum thickness reqired for this process is 50mm which may affect door and ceiling heights.
If you have yet to pour your concrete slab you have more options to customise the look of your polished concrete floor. By adding a decorative aggregate to the new floor (materials in the concrete such as granite, stones, black basalt mix, sea shells or glass), you create a decorative surface when the concrete is honed back.