At last, there is a very low-lead overglaze that prevents devitrification on kiln fired glass projects that is proven safe for food bearing surfaces. Super Spray will not discolor reds, oranges or other sensitive tones. For easy application, simply brush it onto your glass project or spray it on with an air brush or atomizer BEFORE THE FIRST FIRING. Matures at 732C or higher. Super Spray is not designed to FIX existing devitrification.

What is glass devitrification? Glass devitrification is the process by which molten glass is cooled too slowly and thereby becomes crystalline, with a milky appearance, and no longer able to be used as glass.