The stability of a stone installation comes from what is UNDER them, not between them.

If the stones shift, the sand/cement mix cracks and falls apart. If frost gets into the cracks, the mix crumbles and falls apart ...

Laying them on a properly prepared bed of gravel and sand, compacted before the stones hit, then brushing plain sand into the cracks gives the area the best chance of surviving winters.

I didn't pose the question, but thanks, lazygardens. I'm laying a path with scrap granite from a countertop place, and I was thinking about concrete or mortar, mainly because of dreaded bermuda grass. You were a big help to me!

Do a search for Envirobond or organic binder (stay away from polamer) there are plenty of products that will bind the joints - but as Lazygardens states the base prep is the
main priority