How to Iridize a Bottle Before Slumping
- 1). Heat the bottle to 1,000 degrees Fahrenheit in a kiln or with a torch.
- 2). Transport the bottle to a well-ventilated area and wait for the glass to stop glowing.
- 3). Spray the bottle evenly with iridizing spray using an airbrush. A light spray will give the bottle a silver sheen, while heavier sprays will result in more colorful tones.
- 4). Place the glass bottle on the kiln shelf and set the kiln to an annealing schedule. After the bottle anneals, you can set the kiln to a slumping schedule. Slumping the bottle before annealing will cause the iridizing spray to burn off.
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