I have a piece in sterling using rough emeralds. Lots of nooks and crannies plus I want to harden the prongs I used. Can I tumble using steel shot and not have to worry about chipping or cleaving the emeralds? All I have is steel shot for the tumbler.
Matt
Oi-vey! Any stone, no matter how hard, could be chipped by repeated collisions with steel shot and emerald is notorious for cracking, chipping and outright crumbling, as most of it is flawed. Even if it were flawless, because of the expense and the possibility of chipping or breaking, I would not, repeat NOT ever tumble it. I would remove the stones if you have to tumble it to harden the piece or remove the stones and heat harden it. Then you might want to play the torch over the prongs to anneal them enough to make them flexible again so you can reset the stones without breaking the prongs. I think you could restore some malleability to the prongs without disturbing the hardening in most of the piece if you used a small, targeted flame very briefly. Maybe someone with more experience with this kind of work could comment. I just wouldn’t ever tumble any stone in a piece or jewelry…the stone does not have to be softer than the shot to be scratched and chipped. A possible exception would be the ultratough jades, but I’m not even sure about that.
HTH, royjohn
I’d be so very careful with Emeralds! Tumbling them will definitely cause some havoc with these precious stones. Do so at your own risk!!
“gerrysdiamondsettingessays.blogspot.ca”
I’m Gerry, On my iPhone!
Never use a tumbler with stones as all have reported. You can harden your prongs by burnishing them after setting your stones. Just be very careful not to hit the stone.