All materials used in glass products have their own raw material colours, which can be more pronounced with increasing thickness of the glass product. In order to meet the legal requirements with regard to energy saving, coated glasses are used. Even coated glasses have a natural colour. This intrinsic colour can be seen differently when looking through it and/or looking at it. Variations in the colour impression are possible and unavoidable due to the iron oxide content of the glass, the coating process, the coating itself as well as changes in the glass thicknesses and the pane structure.