Red Reactive Transparent Frit is Anything But Plain Frit! The special formulation of Red Reactive frit creates stunning effects in your art by taking advantage of chemistry and heat. As the particles of adjacent frit melt, the elements in Red Reactive Glass respond to neighboring glass containing copper and cause a color change where they meet. This reaction appears as a red-tone line or halo that can vary in intensity depending on copper content, temperature and time. Copper is present in many blue and blue-green glass colors, however not all contain enough copper to cause a noticeable reaction. Click here for a chart to help identify glass that will create the reaction youre looking for. A staple for hot glass artists, you will find frit useful for many applications, including jewelry and casting projects. Frit is made from sheets of System 96 art glass which is crushed, screened, and then packaged in convenient 8.5 oz jars. 96 COE. Glass is transparent. Click View User Manual for more information about this unique glass and a useful reactivity guide to System 96 Colors, courtesy of Uroboros Glass Studios and System 96. Main image shows frit unfired see additional images for square showing the effect of Reactive glass when fused with Fine Sky Blue and Mosaic Turquoise Opal Frit. Frit size can be used to control the opacity of your cast project, the larger the grit the better the clarity as showcased in the frit pyramid shown in additional images. Fine and medium frit are excellent for adding small details to your fused project as shown the nature scenes created by artists Melanie Churchill and Julie Haan. Cast heart box image courtesy of Colour de Verre.