Are there any waste products in the making of PVD coloured stainless steel?

The PVD colouring process on stainless steel does not produce any waste products. There is some waste produced during the cleaning and preparation as water, citric acid and cloths are used. The water is taken away via standard drains, i.e. it is not classed as commercial waste. If natural-fibre cloths are used to clean the material then these can be recycled and add to the sustainability of the process.