There was discussion this past week on ICON about how to clean up sick mineralized glass. I was waiting for someone else to mention another perspective but no one did. The piece pictured, a CD 126 Brookfield, is etched and mineralized in an iridescent white. Amazingly, it is undamaged and is even embossed well. It looks like something Louis Comfort Tiffany could have had a hand in. I don't think any amount of tumbling would make the piece look like new again. But even if it did, what would I have, a $5.00 insulator? I know it is a personal preference, but I would leave mineralized pieces just they way they are.