Vitreous - adj. a) having the nature of, or like glass, glassy. b) derived from or made of glass. Webster's New World Dictionary, Third College Edition.

The prints shown on this page were created at the Harvey Littleton Studios in Spruce Pine, North Carolina. Harvey Littleton, a true innovator and great artist in his own right, and a man of considerable entrepreneurial skills and generosity, is given to making dreams reality for himself and many others. He opened a print studio some years ago, after a successful career as Professor of Art and Department Chair at the University of Wisconsin - Madison in Spruce Pine and invited artists to come and experiment with the vitreographic medium

One of the prime advantages of this medium is color. Unlike metal plates which produce oxidation that contaminate color inks, the glass produces none. As a result colors remain pure and brilliant. The transparency of the matrix offers distinct advantages for placing the plate over a drawing and, allowing for the refraction of the 3/8" matrix, transferring it to the glass with a diamond point needle. Turning the drawing upside down on a light table the print will negate the usual lateral reversal. Carried one step further the initial glass plate may be placed over a second to develop color matrixes, but the standard use of the counter-proof is more accurate and remains the method generally used at the Littleton Studios. Laid on a sheet of black paper the white litho ink technique permits an artist to see, almost exactly, how the print will look when completed. In addition the glass plate will last infinitely longer than copper or zinc. Regardless of the amount of pressure applied or the number of impressions pulled the plate will show no signs of wear. More importantly, the medium has its own unique characteristics which can be exploited for expressive purposes.

Glass under pressure will crack if something beneath it creates a tension point, but with care this can be avoided. This factor also explains why, whether one is dealing with the vitreograph as intaglio or lithograph, it is advisable to use an etching press. Etching presses, unlike their litho counterparts have hard rigid beds which provide a firm inflexible backing for the glass plate.

Many techniques have been compiled at the Littleton Studios which offer the artist great latitude - some a direct carry over from the metal plate and some quite different. A diamond point needle or bit in a flexible shaft drill produces lines similar to drypoint or engraving. Sandblasting, on the other hand, replaces acids and requires a different set of resists. Maskoid, hot glue guns and heavy grease crayons will resist sandblasting and the blaster hose itself, fitted with small points, can be used like an airbrush. For larger areas stencils can be cut from plastic adhesive paper. An interesting process developed at the Littleton Studios is a variant of the lift ground commonly used in etching. The image is brushed on with black acrylic paint and allowed to dry. The plate is then coated quite thickly with acrylic medium. While the medium is still wet the black paint is picked off with tweezers reflecting the brushed mark. Of all the stencil or drawing blockouts developed at this studio, one of the most interesting and versatile is white lithographic ink. Using this material a great variety of tones and textures, quite painterly in character, can be developed. When sandblasted the ink will break down sequentially producing a variety of tones from gray to dense black. It is usually a good idea to check the image on a light table before sandblasting to determine the densities of the ink coating. Ink may also be rolled on the plate thickly and drawn through with sticks or wiped out with rags and solvents to create a subtractive image. It offers great flexibility and beautiful painterly effects.

The normal pressure used for blasting at the Littleton Studios is 60 pounds (U.S.). Holding nozzle well back from plate, apply a light coating of silica. This is particularly important if the resist is a soft wet material, ie. white litho ink because it is the combination of the ink and the coating of sand that creates the resist. Moving the nozzle closer to the plate continue blasting until resist begins to disintegrate. Stop periodically to check the plate. Course sand mixtures will produce a quality similar to a course aquatint while fine carborundum grains will have the effect of a box aquatint.

Subtler tones can be made by etching or frosting the glass with a material called Jack Frost. In contact with glass this rather gritty liquid will produce a 2% Hydrofluoric Acid solution that can be brushed on the plate much like a watercolor wash. The resulting tonal range is from light to medium gray. Some control can be had by diluting the Jack Frost with water or by the amount of time, up to three minutes, that it is left on the plate. After that time it loses much of it potency.

Following these procedures, rinse the plate and clean with mineral spirits. Safety precautions must be taken with this material but the lovely wash effects are a distinct contrast to sandblasting and make it worth the effort. Both silica sand and hydrofluoric acid are hazardous materials and should only be used in well ventilated places with heavy rubber gloves and a good fume mask. Finally clean the plate with mineral spirits followed by a 1:1 vinegar water solution to remove greasy residues.

To avoid cracking the glass the press bed must be extremely smooth and clean. You can ascertain this by feeling the entire bed with your finger tips and removing any burr with small flat file. Polish the bed with fine steel wool and car wax and finish with rags and with mineral spirits, followed by a 1:1 vinegar and water solution. Finally spray the entire bed with silicone spray,

An interesting innovation at the Littleton Studios are the press templates which hold the plate in place and serve as convenient color registration forms. While a separate template must be made for each size plate, they are relatively easy to prepare. Cut two pieces of tempered masonite (one 1/4", one 1/8" thick to equal the glass thickness) wider than the paper normally used and about twelve inches longer. Glue together with contact cement and cut a window in the center about 1/8" larger than the plate. Seal the template with silicone spray to protect it from moisture and inks. Place the template on press bed and hook under the press roller along with the printing blankets.

This procedure is both similar and different than preparing a metal plate but it has proven itself over and over again at the Littleton Studios. Clean the glass plate thoroughly with mineral spirits followed by 1:1 vinegar and water solution. Ink and wipe the plate as you would for any intaglio. Glass plates hold very little film and the finishing wipe may be accomplished with tissue to remove all ink film if that is desired. Check the press bed in the template window for dirt or grit by holding your hand flat and feeling every square inch of the bed.

The next step is different than the metal version and critically important, Stand the plate on its side with the back facing you. With the hand held flat feel the back of the plate. When you are certain that the back is immaculate take it to the press bed. Slide the plate into the template window, Pressing down with your fingers, move the plate back and forth listening for gritty sounds. If a sound is heard repeat the cleaning process. When you are satisfied that everything is right, push the plate into one corner of the form and drop into the window. A shim made of balsawood trimmed to the thickness of the template will hold the plate tightly in place if you feel the need. Lay paper and print. When printing color plates, Judith O'Rourke, Master Printer at the Littleton Studio will leave the paper firmly hooked under the press roller while changing plates.

When the printing session is complete, clean the plate well with mineral spirits and vinegar water to remove all ink. This is important, particularly with sand blasted plates. Where the sand hits the plate it produces a tiny pit. Below the pit even smaller cracks occur. Ink penetrating into these cracks will, if allowed to dry, cause the plate to produce lighter impressions in subsequent printing.

Excerpted from an article I wrote for Printmaking Today, Vol. 3, Number 3, Autumn 1994. Published by Farrand Press. 50, Ferry Street, London E14 3DT, UK