Early Colored Clay Work

This gallery includes colored clay sculptural work and large pictorial platters done over a nine-year period from the start of my graduate studies at UMass-Amherst in 1985 until I was hired at the Appalachian Center for Craft in 1994.  Discovering the possibilities of colored clay marquetry was among the more exciting things I have experienced, and it kept me enthralled for about twenty years.

Upon arriving in grad school in 1985, it made no sense to just continue with the slip-decorated functional vessels that were my best work in California and got me into grad school.  In a conversation with my primary graduate professor Frank Ozereko, I spoke of my appreciation for the depth and solidity of color in slip-decoration.  Frank pointed me towards colored clays and suggested I look at the work of Jane Peiser. This was long before the Internet, but I found her intricately-decorated colored clay vessels in the first Penland Pottery Book, published in 1975. I had never seen anything like it and was inspired.

Other than a few tantalizing bits of process described in the book, I could find little technical information about colored clay techniques.  As a result, I started from scratch and figured it out for myself. That often works very well when investigating an unfamiliar technical process, because it activates creative imagination.  You automatically adapt to your own aesthetic preferences and ways of working, making the process your own.

Scroll down below the images for technical information about the colored clay work.  Email me if you have questions. Click on thumbnails to see a larger image.  On a computer, once you’ve enlarged the image, scrolling works best with the left and right arrow buttons on your keyboard. On a phone or tablet, tap on the right-hand or left-hand edge of the enlarged image.  Click or tap the little square in the upper right of the enlarged image to magnify and see details.

Technical Information

All of my colored clay work starts with a white earthenware claybody of my own design, with Mason brand ceramic stains added for color.  While doing this work I maintained an extensive library of blocks of colored clays, and I cut and combined those clays in complex ways to build patterned murrini loaves with the pattern passing all the way through the loaf.  Patterns include masonry (red brick, yellow brick, stone wall, slate roof, etc.), basket-weave, herringbone, checkerboard, polka-dot, parquet, wood-grain, granite, marble, and many others.  A few sample loaves are pictured below.

With much East Asian and British colored clay work, the color goes all the way through the wall of the vessel, and thus a considerable amount of colored clay is used in every piece.  From the start I used a lamination process. With a flat-bed slicer of my own design, I can cut veneer slices as thin as 1/32″ from solid or patterned loaves.  I laminate those veneer slices or pieces cut from slices onto slabs or coil-built vessels, so I get a great deal of mileage out of each patterned loaf.  As you can see in the images, most of the work involves a mixture of patterned and solid-color laminations.

In the pieces involving pictorial imagery, I draw the original image to size on posterboard and label every individual area with an identifying number and codes for the intended color or pattern of clay.  I make a Xerox copy of the image to get a working drawing so I’ll know where to put all the pieces.  With a stencil knife I cut up the posterboard original into individual template pieces, often hundreds of them.  The templates are used to cut out all the component parts from veneer slices of the appropriate patterned or solid-color clay loaves.  For cutting clay pieces using the posterboard templates, I place a veneer slice of the desired color or pattern on canvas, lay the template on top, and cut around the template using a homemade needle tool equipped with a very fine sewing needle.  The tip of the needle is dulled slightly with sandpaper so it doesn’t snag badly on the canvas.

When laminating veneer onto a slab that will become a platter or sculptural piece, I give the surface of the slab a misting with water containing a bit of vinegar, and lay the lamination in place.  Assembling a complex pictorial image as you see in the platters and some other pieces is a little like assembling a jig-saw puzzle composed of wet noodles, and can take thirty or forty hours to complete one image.  The slab is always covered with plastic except when I am laying a veneer piece in place, and I mist frequently to keep it moist.  All but the largest veneer pieces are best handled with the same homemade needle tool mentioned above.

When all laminations are in place, I smooth an appropriate piece of damp canvas over the whole slab and roll it quite aggressively with a large rolling pin to guarantee that all laminations are well-affixed.  As long as the canvas is smoothed down and stuck to the surface, the image will not shift at all.  After compressing, I carefully lift the canvas from the compressed slab, and this actually removes some of the surface distortion, leaving a cleaner, more distinct image.

For a platter, I slide the canvas-backed slab onto a large round bat, carefully place a large plaster hump mold face-down in the center, and flip the whole thing over so that the slab slumps down against the mold when I peel away the canvas.  I center the hump mold on a pottery wheel and gently work the backside with a rib to ensure that it is hugging the hump mold.  I trim the outer edge of the platter and add several concentric coil-thrown foot rings.  For a sculptural piece or geometric vessel, I allow the slabs to stiffen to medium-leather-hard, cut them into pieces with a dulled X-Acto knife, and assemble.

For the large coil-built pieces seen on the Colored Clay Vessels page, I use a standard serrated rib to lightly score a crosshatch pattern in the leather-hard surface of the completed vessel.  I mist with vinegar water (1/2″ of vinegar in the bottom of a spray bottle, fill with water), gently put the lamination in place, smooth a small piece of canvas over it, and gently roll with a small, soft printmaking brayer.  This process is repeated with every lamination to build up the imagery or pattern across the surface.

In most colored clay work, once lamination or assembly is completed the entire surface must be cleaned of smearing and distortion to sharpen up details of the imagery or patterns.  With pieces that have an irregular form and/or raised relief, I carefully scrape the surface at the hard-leather-hard stage with a variety of metal scraping tools adapted for this purpose, including wood chisels, razor blades, metal ribs, etc. For pieces with an overall smooth surface, my scraper of choice is the standard flexible kidney-shaped stainless steel rib, although smooth-surface pieces can also be lightly sanded at the bone-dry stage with a green Scotchbrite scrubby pad or fine-grit drywall sanding mesh.

After bisque-firing, black underglaze is applied to some of the pieces for shading and detail, and the work is glazed with a commercial lowfire clear glaze, generally applied with a spray gun and/or airbrush. No other glazes or underglazes are used, and all of the color you see is colored clay. I was hooked on Duncan GL-611 clear glaze and used it exclusively on all of the work done between 1985 and 1991, but it is a leaded clear and no longer available. I was frustrated in trying to find a reliable clear that would give a consistent transparent gloss over all of the colored clays, but several people have recommended Amaco LG-10.  When I get back to doing colored clay work, I’ll give it a try.

The clear glaze is applied variably depending on the desired surface effect. In pieces such as the Industrial Shard series, I just want to enhance the colors without any gloss, and in that case I dilute the clear glaze with water and spray on a very thin coat. On Steam Shrine, the overall structure received such a coat, while the pictorial panels were glazed in a normal fashion to maximize the color clarity and intensity. On For Rube Goldberg: Perpetual Motion, the “window” of imagery and the surrounding brick face are on the same plane, but the window was masked off and sprayed with a normal coat of clear glaze.  Once the masking was removed, the whole piece received the thin diluted coat.

Mixed-Media Work

Most of my early colored clay work was fired to cone-03 in oxidation in toploader electric kilns. Many pieces in the “Industrial Shard” series include actual black iron pipe, steel wire, and/or threaded steel rod.  These metal components were fired in-place with the work to cone-08, resulting in a blackened, oxidized finish on the metal.

20th Century Limited: Sheeler’s Station, Past/Future, and The Riggs Patented Wonder Engine incorporate bronze hand-wheels, flywheels, and/or flanged railroad wheels that I cast in the UMass-Amherst sculptor’s foundry.  All of the wheel shapes were initially drawn on posterboard, cut out with a stencil knife, traced onto Masonite, and cut out with a very fine-blade scroll saw.  I added thicknesses of matboard to create the raised center hubs and rims on the flywheels and hand-wheels, and the track flanges on the railroad wheels.  Wherever necessary, I shaped the Masonite with files, die-grinder, and sandpaper to give appropriately rounded edges, such as on wheel spokes.  For casting, I gave all the wheels a thin overall dip-coat of microcrystalline casting wax and then connected multiple wheels in groupings with microcrystalline wax sprues, vents, and a pouring cup on each group.  I encased each connected group in a ceramic shell mold, burned them out in a crucible furnace, and poured the molds with bronze.  Burning out the molds in a crucible furnace brings them up to bright red heat very quickly, and the ceramic shell mold can take it.  All organic material in the mold is vaporized or burnt to ash, and several quick blasts of compressed air after burnout blow out all the ash before pouring the bronze.

After cutting and grinding away all the sprues, brazing up some casting flaws, and cleaning up the surfaces, I applied patinas to make the bronze look appropriately antique.  Images of the ceramic shell molds, rough castings, and finished castings are included above.

Colored Clay Terminology

There is some confusion over terminology in colored clay work. The traditional Japanese terms neriage and nerikomi often seem interchangeable.  I have seen neriage frequently used in reference to handbuilt work, and nerikomi to wheel-thrown forms.  Thomas Hoadley says the opposite is true, and that in Japan, neriage most accurately refers to use of colored clays in thrown work.  Both terms usually refer to work where the colored clay passes through the vessel walls and the pattern or imagery is visible both inside and outside.

The term murrini refers to an Italian art glass technique where colored rods or shapes are combined in a larger mass to create pattern or imagery, fused together, and cross-cut into many pieces showing the same pattern or imagery. The term has been appropriated as colored clay murrini in reference to the similar method for making loaves of patterned colored clay such as those pictured below.

The term marquetry normally applies to woodwork where small pieces of wood are laminated onto the surface of furniture or sculpture to create intricate overall pattern or imagery, and the term has been appropriated to describe the similar technique in clay.  If small areas of an otherwise undisturbed clay surface are excavated and inlaid with colored clay pattern or imagery that becomes flush with the original surface, the method is referred to as inlaid colored clay.  If the piece is laminated overall with pattern or pictorial imagery composed of many small pieces put in place separately or from patterned loaves, the technique is colored clay marquetry.  If the piece is laminated overall with solid-colored clay, then it is laminated with colored clays.  Colored clay murrini refers to the loaf construction.  It can be all confusing, and sometimes I find myself using the terms interchangeably.  Please email me if you have questions.

Selection of Patterned Colored Clay Murrini Loaves