Harmony through Oxidation
These surface changes may be utilized to harmonize metal and its environment, as, for example, copper trimmings and a shade for a pottery lamp; or it may be used to reduce the brightness of the natural copper surface.
The surfaces of metals may be changed with actual manipulation of the surface by frosting or sanding and plating. Gold may be readily plated with gold to bring it into closer harmony with the stone. Plating, applied to base metals, merely to give the impression of a more expensive metal, is to be discouraged.
Metal Backgrounds
One has to consider metal as a background in much the same manner as we considered wall surfaces as a background for stained furniture. Whatever color is applied to the surface must harmonize in proportionate distribution as well as hue, value, and chroma. We have a small amount of leeway for varying the background by the different processes of oxidation and plating.
Enamel on a Copper Background
As one of the more common processes, let us consider the application of enamel to copper in the form of champleve enrichment. Our first thought would be the analysis of the natural copper color. It is found to be a shade of orange-red and will, therefore, readily harmonize with the analogous oranges and reds, as they both have the common hue of red. There should be a slight contrast of value between these enamels and the background. If this contrast is not present, it is well to oxidize slightly the copper to lower its value and thus produce the contrast.
Complementary Arrangement
The fourth harmonious hue combination, that of complementary arrangement or grouping, has been left to the last as its use is more closely associated with small multi-colored projects and small areas. A hue approximately complementary to the initial hue is found by counting seven rectangles to the right or left of that hue; this will give the hue complementary to the initial hue. Thus, starting with red and moving through seven rectangles toward the right, we find the complement to be green. Any two hues so selected will be found to enhance the brilliancy of each other. The best results are secured when one hue dominates the color scheme by its increased area. Pottery may be adapted to a complementary color scheme by Rule 12i.
Rule 12o. Small one or two-hued projects in clay, designed to be used as a part of the decorative color scheme for a room should bear a contrasted, dominant, analogous, or complementary relation to the side walls of the room. The project may be much higher in chroma than the side walls.