Hi Steve,
Many thanks for your detailed and informative response.
I used to buy cabochons from a stone supplier in Jaipur in India a good few years ago. Having bought the stones I then had them mounted by a team of artisans who transformed them into pendants. Over the last few years I've changed the focus of the business to rocks and minerals and moved away from jewellery which is why I started removing the stones from the settings. I had hundreds of pendants that I really didn't want to waste more time with because I only trade online so everything needs to be photographed individually, uploaded to my website etc etc.
I have no idea whether the stones would have been treated prior to me buying them and if they have, how. I also have no idea what kind of adhesive would have been used to fix them into the settings. It is just the adhesive which is a very hard substance around the edge of the cabs that I need to remove. It comes away easily when I sand with wet and dry but of course it also removes the polish.
There's a wide assortment of stones such as agate, jaspers, lapis, feldspars, larimar, turquoise etc. Some are more valuable than others so I'm happy to do those by hand but with regards to the cheaper stones I'll give acetone a try. To be totally honest, if I lose a few it's not the end of the world, of course I would prefer not to but it's certainly worth a go. I'll chose stones carefully and won't include turquoise, malachite and anything that's porous or too soft. Eudialyte I think may get damaged so I'll skip on those as well.
I'll be selling them to recoup some of my money but will make it clear that some may benefit from additional polishing around the edges. They'll be sold at knockdown prices but I can't sell them with the residue.
Thanks again for the advice.
Regards,
Laurence