Divitrification After a Full-Fuse Firing


Have you ever noticed ugly, hazy, gray coloration around the edges of your full-fused designs? This is especially noticeable when placing darker colored or iridized glass designs on a lighter colored background but it can happen with any color combination. This phenomenon is known as edge-devit (devitrification) and is most often caused by grinding the glass edges prior to fusing. This also occurs when using a diamond blade saw to cut your glass.

One glass manufacturer explains it this way; The roughened edges in the ground area create thousands of tiny points from which crystal growth can easily propagate. The best solution is to score and break the glass as close to your final shape as possible to minimize grinding (or better yet avoid it altogether).

If you must grind you could try using a light coat of clear overglaze (i.e. Fusemaster Super Spray) on the ground areas to create a clear surface glaze.

This Randys ProTip brought to you by the book, Introduction to Glass Fusing by Petra Kaiser. Visit Wardell Publications.

Be the first to comment.
Randy Wardell

Randy Wardell

Randy Wardell has been in the art glass industry for more than 30 years and has done it all, from teaching to selling retail supplies and running a custom glass studio, to managing a major glass wholesale warehouse. In 1983 he founded Wardell Publications Inc. to produce instruction and pattern books for the glass craft industry. Randy is the author of 10 books and his company has created and released more than 50 published products into the market. He is a writer, editor and frequent contributor to glass craft magazines and informational websites.