Colorful Clay
Color-body Porcelain Mosaics for the Masses
You may have seen them under foot. Perhaps in the vestibule of an old drug store or apartment building. Maybe it was the elegant script that caught your eye or maybe it was the colorful border. Regardless, you stopped to admire them: the color-body porcelain mosaics.
Figure 1. Color-body porcelain mosaic entry vestibule sign in Snohomish, Washington. (Credit: flickr/Jasperdo)
Color-body (or through-body) porcelain mosaics, popular from around 1880 to 1950, have roots in the mosaic traditions of ancient Rome. But, unlike the Romans who primarily used stone and pigmented glass to create their mosaics, these are crafted from pigmented clay. It is precisely that integral color, derived from pigments mixed into the clay and running throughout the body of the tiles, that makes these mosaics so suitable for use in floors (Figure 1). The color remains as the surface wears down with foot traffic. What’s more, color-body porcelain mosaics are fired to the point of vitrification, making them extremely durable and resistant to moisture absorption, frost, scratching, acid, and impact. These mosaics are just as suitable for outdoor use as they are for interior decoration.
Figure 2. Tile press for mosaic tiles using the dust-pressed process.
Early color-body mosaics were imported to the United States from manufacturers in Europe. There, tile manufacturers had adapted a new ceramics fabrication technique, called the “dust-pressed” process, from making buttons for clothes to making durable tiles. In the “dust-pressed” process, ultrafine kaolin clay with a relatively low moisture content was pressed between two metal dies to produce the desired shape (Figure 2). This eliminated the need for drying the un-fired or “green” tiles before they entered the kiln, speeding up production and reducing costs. By the early 20th century, American entrepreneurs had adopted the dust-pressed process and domestic tile production exploded.
Figure 3. Pre-made mosaic borders from the American Encaustic Tiling Co. catalog (c. 1900). Note combinations of circular, square, and hexagonal tesserae.
While the dust-pressed process made mosaic tiles cheaper to produce, it also led to standardized tile (or “tesserae”) shapes including circle, square, hexagonal, rhomboid and diamond shapes. Mosaic sheets, ordered from a catalog and delivered pre-mounted on a glue and paper facing ready to install, made these new mass-produced mosaics available to the burgeoning middle class and eliminated the need for skilled mosaic artisans to perform the work (Figure 3).
Color-body mosaics were most often installed as flooring and usually had a decorative border, although borders eventually fell out of style in the 1930s and later installations were more commonly comprised of one or two tesserae colors. Less commonly, color-body mosaics were also used as a wall finish. Perhaps the best examples of this are found in the earliest New York City subway stations. There, subway designers employed these durable mosaics in wall signage identifying station names and as accents to other tile finishes (Figure 4). Early subway mosaics were fashioned in the Roman style, meaning the tesserae were cut or broken from larger stock rather than being molded in their final shape (Figure 5).
Figure 4. Borough Hall Station (built 1908) features elaborate glazed and unglazed color-body porcelain mosaics combined with marble wainscoting, a terra cotta cornice, and white glass field tiles to produce a particularly rich decorative scheme.
Figure 5. Detail of Borough Hall station name tablet showing "Roman" style mosaic tesserae that are formed as strips of porcelain and then broken into random lengths.
Today, color-body porcelain mosaics have had a small resurgence in popularity. Large tile manufactures like Dal Tile and American Olean offer limited shapes and colors and are available through most suppliers. Boutique manufacturers like Winkleman’s in Paris and American Restoration Tile in Little Rock, Arkansas, offer accurate historical reproductions and do custom work such as mosaic signs and matching existing colors (Figure 6).
Figure 6. Reproduction of historic mosaic tile floor in a Kansas City, MO, hotel lobby. (Credit: American Restoration Tile)