It is also possible to alter the natural color of materials. During the Renaissance, natural stone was dyed. This technique is no longer common due to the wide range of colorful materials available on today’s market. Binding agents and additives used in the making of artificial stone are often dyed.

Wood is stained, glazed, or varnished to varying degrees of opacity. For ceramics and stoneware, there are stains and glazes with a variety of surface qualities ranging from smooth to textured, and from matt to high gloss. Metals can be galvanized or coated, for example, chromed, nickel-plated, brassplated or anodized, but they can also be enameled or coated with epoxy resin. Each of these surfaces has a very different look and feel. The function and use of a material in interior design depends on whether or not it is intended to represent itself or serve as an accent in a composition, whether it should act as the dominant element of an ensemble, or harmonize as a single voice of a “choir.” Materials can have a natural and characteristic color and texture, or they can be processed and fundamentally changed. With its individual character and unique color, as well as its own texture, each material represents a distinctive image. The inherent image of the material, its “visual value” or “aesthetics beyond its practical value,” can be altered through processing. The effect this has and the atmospheric impression it makes on the individual – warm or cold, pleasant, luxurious or majestic – depends on the socialization of the individual. Hence, each material conveys a message.

Colors vary in their effects according to the application technique used and the material substrate. Many aspects of coating techniques are dealt with here.There is an abundance of specialized publications available that deal with technological issues.

Color applications (paints, glazes, etc.) are coatings of walls, ceilings, and floor surfaces, as well as objects made of a wide range of materials including wood, metal, plaster, mortar, masonry, concrete, plastic, glass, fabric, and paper.

Absorbency and surface structure (texture and processing method) have a major influence on how an object’s color is perceived. Similarly to materials, surface characteristics in combination with the color itself, and its position in the overall color scheme, work to create a value, an image impression.

Until very recently, only “immaculate” flat and opaque coatings were generally accepted as being suitable for architecture. With today’s growing environmental awareness, however, traditional materials and application techniques are making a comeback. Using natural pigments and binding agents, glazes are becoming very “presentable.” Old encaustic wax painting techniques and trowel lacquer applications offer interesting color mixing possibilities and, with their various colored layers, they produce rhythmically textured and vibrant surfaces. By working with colored surfaces and natural materials, as well as color applications and material surfaces, designers have a wide array of possibilities to create exciting spaces. In the interest of each specific spatial function and atmosphere, however, it is recommended that they take a disciplined approach to the full range of possible effects. Often the individual value of a surface can best be enhanced by toning down its surroundings. Diverse textures and processing methods often detract from individual elements and can be visually overpowering.