I wouldn't hesitate. I've used glass, dish shards, all kinds of junk in stepping stones and bricks for my mosaiced path. IMO, you don't have a thing to worry about. Just remember, stepping stones need a bit of texture so they aren't slippery.

I ditto what Slow says, I have used smooth tile and had it slippery, so make sure your feature has some texture...unless you plan on using it just for looks. I had to move one to a place that it doesn't really get walked on a lot to enjoy it, but you live and learn!

Thanks, Slow and Calam, for your input! I'll have to add some pottery pieces and dish shards to give them some texture because I do want to be able to walk on them.

Yes! I stuck a 4X4 glossy tile in the center of one of my stepping stones and almost broke my ankle sliding across the thing one wet day. I've always wondered about those beautiful stepping stones made using large pieces of stained glass. I now keep my pieces on the smaller side.