How to tumble rough Ruby Sapphire and Others

Hi dbaur! Welcome to the forum!!!

If I were you, I'd tumble the Amethyst and Citrine together. In a separate batch, I'd tumble the Emeralds, Rubies and Sapphires.

The best place to get grits is The Rock Shed....http://www.therockshed.com/

You don't need any diamond paste for these. A wash in Borax (which you can get at your local grocery store in the laundry section) is recommended between each grit stage.

I would recommend using either plastic pellets or ceramic media. The Rock Shed carries both.

Hi dbaur,

As someone who has tumbled more gemstone than agate to date, I'd also say start with something a little easier than especially the ruby/sapphire, <grin>. Wouldn't want you to get discouraged before you're well and truly hooked...

Of what I've done so far, the best results I've gotten have been citrine and topaz, and I've seen some great results others have had with garnet as well. The emeralds I've done have also come out pretty well, but being opaque and buried in matrix like they are they're not quite as good a result as the topaz and citrine have been. The amethyst I've gotten to date has been full of fractures and I haven't gotten much to brag about from those - maybe ten fairly nice stones out of 80-odd.

My ruby/sapphire tumbling results are just a few threads down on this page - and they've been tumbling off and on for nine months or so. The kind of ruby and sapphire that you get in these 'mine-run' mixes are not facet grade, they are completely opaque and at best are the variety that may star if cabbed rather than turn up clear like a stone you'd facet. Tumbled rather than cabbed, what I'm seeing with mine is that at some angles (especially when wet) you get a bit of 'depth' to the stone, and a bit of shimmer from [what I assume are] the layers of alumina - sort of like what you get from Labradorite or Moonstone, but not as flashy or colorful as Labradorite. I'll do my best one of these days to capture on camera what my eye can see.

The only stones you'd need anything diamond for would be the corundum (ruby/sapphire), and then only for the later stages - the emeralds, citrine and amethyst can be done just fine with regular grits and polishes, and the regular SC coarse and medium grits do a pretty good job for the early stages on the corundum as well. I've got a split experiment running right now, with some of the corundum in a tumbler with diamond paste (powder would have been fine too, just that you usually get more diamond per ml/gm in the paste than in a powder), and some in just regular polish or pre-polish. I am seeing some shine on the flatter areas with the ones that are in regular polish after a month of being in there (compared to a day or two for most other stones in a Lot-O at the polish stage), but it's nothing spectacular and I expect that I'd have to leave them in that polish for another six to nine months before they looked anything like polished stones on every side.

The ones in the diamond run are faring a bit better, have shown quite a bit of improvement in the week or so they've been running. I'll take some more pics in a couple of days. They're in a very small (1.1lb) vibe tumbler, btw - I wouldn't myself have wanted to try this with diamond in a 3lb rotary or 4+lb vibe, because it would get *very* expensive. I don't have any idea what diamond's breakdown rate is as compared to SC (for grit-renewal purposes), but even the initial amount needed would be fairly pricey. I want to say that I paid around $60 incl tax/ship for three 5-ml syringes (one 4k, one 14k, and one 50k mesh), and I'd think it would take most of one syringe to charge a 3lb or up tumbler just one time.

I probably wouldn't have taken on the corundum (or would have given up on it long before now) if I hadn't had other tumblers working on things that give better and faster results. Or if I hadn't had a Chicago Electric whose days I already knew were numbered without upgrading the motor, fan and pulley (I did change out the belt, pretty much a must with any CE as the ones they come with don't last) to put them in. It lasted long enough to get the corundum through coarse and medium, and having them there didn't hinder my progress on anything else, so it wasn't a particular hardship or trying-of-patience to have those taking up a barrel on that particular tumbler for that long. But if you're planning on doing them in one dual rotary, I'd definitely recommend starting with something that will show results a lot faster than corundum will.