Reactions
When we refer to a “reaction” in glass fusing, we are talking about what happens when different glasses have a chemical reaction with each other. When a reaction occurs, a brown line forms between two pieces of glass that are fired alongside each other. This shift in color where the glass touches is caused by a reaction between metals in the glass. Various metals are used when making glass such as lead, copper, selenium and sulfur. Glass that is made with a copper molecule will react with glass that contains selenium/sulfur.
Aspiring glass artists typically want to eliminate any possibility of reactions. Students often express dismay when they open the kiln and see that their perfectly planned project has an unplanned reaction. With knowledge and planning, that disaster can turn into a beautiful project. Much of Susan’s current work involves creating reactions and using them as design components. Check out some of the examples on this page and the Class Page on this web site if you are interested in learning more about reactions.
The piece on the right is made of taupe and Bullseye French Vanilla glass. These two pieces were first cut to form an adjoining edge and laid flat on the same plane. Then turquoise frit was sprinkled along the seam and the piece went through a full fuse firing.
The white stripe between the two adjoining pieces is a characteristic of the Bullseye French Vanilla glass which forms a white stripe after it is fired. The brown color surrounding the turquoise frit is the result of a reaction.
This piece was made from alternating strips of turquoise with two shades of orange glass (one is almost a red color). Then turquoise circles were inlayed into the orange glass.
After firing, a reaction occurred between the turquoise and orange glass forming the brown outlines. Notice that no reaction occurred where the two colors of orange glass join.
The visual reaction seen between two pieces of glass does not always appear after the first firing, it could show after a second or even third firing.
In the picture on the right, brown glass frit and turquoise were used. During the second firing process the turquoise reaction with the brown glass became the most visible, giving the brown glass a dark outline.
This piece is made up of strips of French Vanilla, clear and white glass with two layers of turquoise. This is an end view of the glass and ten to twelve layers can be seen. A glass saw was used to slice the glass block into many similar but unique pieces. After firing, a brown reaction line can be seen between the turquoise and French Vanilla glass as well as between the French Vanilla and white glass.
The outside strips in this piece are made from strips of the French Vanilla glass. In this example the only reaction that occurs is inside the gray square. Strips of white, black and French Vanilla glass were placed inside a border of blue-tint glass.
The inlayed piece was fired to a temperature of 1700 degrees and while it was still hot, a combing technique was used to create the swirl pattern. Brown lines between the white and the French Vanilla glass formed as the metals in each type of glass reacted with each other.
This is a side view of layers of clear glass with white running through it intermixed with a layer of white, French Vanilla and turquoise. After firing, the reaction between the French Vanilla and turquoise can be seen.