Understanding FIRESCALE can be a mystery. Designer Craftsman Jeweler Greg Greenwood, explains what Firescale on Sterling Silver is. How you get it. Once you've got it - what to do about it. And how to prevent it. Firescale can be confusing and frustrating. Greg takes you through all the questions about Firescale and makes it understandable. FINALLY, you will know what causes Firescale and how to prevent it on your Sterling silver jewelry projects.