What metals can I tumble?

I have tumbled sterling silver, stainless steel, copper and brass. Using stainless steel shot the stainless steel chains will be burnished but not to a mirror shiny finish. To get that finish on stainless you will need to use a different material instead of the shot. I don't ever tumble trigger clasps or slider clasps as I think the liquid could degrade the inside springs.

What stones can I tumble?

I haven't tumbled pieces with turquoise or pearls because I have read this can damage the nacre on the pearl and the turquoise being porous may absorb the liquid. I tumble the chains before I add these stones. I have tumbled amber without a problem but I only did this for about 20mins. Glass and Swarovski crystals have been fine. Hard stones like quartz and chalcedony seem fine but if I'm worried I tumble one bead first just to see what happens, make sure you put the bead on scrap wire so the little stainless steel balls don't get stuck inside.

How Long?

I only tumble small amounts at a time, just because that suits my workflow. I usually check my pieces after 30-40 minutes and see if they need more time. The time will probably depend on what material and how much volume you are tumbling.

How do I store it?

When I have finished tumbling I rinse the barrel and stainless steel shot and then I cover the shot with filtered water with the water about an inch above the shot, all ready to use for next time. I tighten the lid and just leave it standing upright. I don't dry the shot and I have not had any problems working this way for over 2 years with the same stainless steel shot.