Pâte de verre is one of the oldest and simplest of glass-working techniques. But at the same time, it is also one of the most challenging. The challenge comes from the nature of glass itself, which is both a liquid and a solid. When molten it likes to round up rather than flow. Colored with metallic salts and oxides, each batch is unique, changed minutely by minute changes and impurities in its ingredients. So combining different colors in the presence of plaster, moisture, and varied amounts of air always results in at least a bit of unpredictability. The more complex the form, the more surprises are to be expected. Glass is a magical substance, and pâte de verre is the most mysterious way to manipulate it.

Pâte de verre basics
Powdered glass is poured into a mold that is heated in a kiln. As the glass melts, more powdered glass is added to the mold until it is full. The air trapped between the melting granules of glass gives pâte de verre its characteristic cloudy finish and its satiny, soft look.

Despite the simplicity of the basic technique, pâte de verre is not widely practiced because it is also one of the most challenging of glass-working techniques. Each piece starts as a wax sculpture or form. The wax is encased in a plaster mold and then expelled, "lost," by being burned or steamed out of the plaster mold. Finally, the plaster mold is filled with powdered or ground glass and heated in a kiln. The piece undergoes heating at different temperatures then annealing and slow cooling in the kiln. Once cooled to room temperature, the artist removes the mold from the kiln and carefully pries away all the plaster. Final finishing involves grinding on a diamond wheel.

Many things can go wrong at any stage in the process. Glass can seep throughout the plaster, or the plaster can become permanently fused to the glass. Parts of the mold may not fill. Stress faults can develop if cooling is not slow enough or the shape is too challenging. The glass may break when the plaster is being removed. Or the piece may be grabbed by the grinder and flung into a wall.

Looking at most pâte de verre, you’ll notice that pieces tend to be solid and thick with low sculptural relief. Originals with these characteristics can be used to make reproducible molds. This makes the time-consuming process more economically viable since a piece can be cast over and over with reasonably consistent results.

What makes my pâte de verre different?
My version of pâte de verre is unique. Because each of my pieces is fully three-dimensional, characterized by wafer-thin areas, trapped negative space, and extreme undercuts, no permanent mold can be made and each piece is truly one-of-a kind. It is also much more fragile than a solid lump of glass would be, but I find it immensely more beautiful and fulfilling.

Pursuing self-expression in the medium of pâte de verre has taught me things I never suspected about myself. Although a perfectionist, I enjoy responding to the unexpected and am excited by the surprising color effects that occur when different colors of glass combine in different proportions and are subjected to varied chemical reactions with each other, plaster, moisture, and air. I like the imperfect surface left by my fingerprints and the color variations that result from imprecise measuring and mixing. Such imperfections seem to capture the fleeting nature of the images and emotions that inform my sculptures.

I love the delayed gratification of a piece being in the kiln for a week or longer and the surprises that come when I disrobe it from the plaster, having forgotten exactly what the wax looked like.

Above all I love the challenge of nudging glass to perform the impossible and defy gravity or penetrate into impossibly narrow places. There is always something new to learn about this medium or some challenge to overcome. I will never exhaust the possibilities of pâte de verre or understand all of its mysteries. Over the years, I have worked up from a success ratio of about 20% in the beginning to about 85% today.

A certain amount of failure is desirable; it means I am still pushing the limits. As I was modeling Spirals, 2004, I said to myself, "You crazy woman, there's no way these tiny spirals can ever fill. You might as well just mush up the wax and start over." But then another part of my mind said, "Well, the worst that can happen is failure - let's just see." I was dumbfounded when the plaster came off and all the spirals had filled, as well as everything else - including the many places where the glass had to flow up.