The artist adds black line work to the medallion to define the particular scene. The medallion is then kiln-fired at 1,200 degrees Fahrenheit to permanently set the paint to the glass.
Artists then carefully shade the scene by hand using monochrome glass paint. This adds visual depth to the image by emphasizing light and shadow. Another firing in the kiln sets this shading paint.
Next, color is added to the medallion using a palette of glass paint: artists again paint each color by hand. The medallion is kiln-fired for a third time to permanently set the color paints.
Finally, skilled craftspeople inspect the medallion for quality before glazing it into the new stained-glass window.