Glass-on-glass printing is a recent development in fused glass, created largely by artists with printmaking backgrounds who experimented, practiced, and shared their knowledge with each other and with the rest of us. The process involves silkscreens, powdered glass, heat, and time.
Here’s the short explanation of my process: I edit a photo to create separate images for each color or shade of gray that will be in the final piece. The images are printed with black ink onto transparent film. I expose each of these film positives onto a photo-emulsion-coated silkscreen with UV light.
The exposed silkscreens are stencils. I carefully place the first silkscreen over the background sheet glass, pour powdered glass along one edge, and pull the powder across the screen with a cardboard squeegee. The more times I pull the powder across the screen, the deeper it piles up on the glass below, intensifying the color. When I’m done with one silkscreen pattern, I repeat the process with a different silkscreen for the next color.
Once all the colors for a firing are screened onto the background, I add any decorations, such as hair beads for the little girl in “At the Well,” and transfer the piece to the kiln. For some pieces, all the colors are fused in a single firing. Most pieces are fired at least twice, with some, like the papercut plates, taking four or more trips through the kiln. Time and temperature of the firing program determine the texture and even the apparent colors in the final piece.