i just laid a small L-shaped landing underneath a fence gate using sandstone fieldstone. nothing fancy, just something to walk on through the gate so i don't have to mow there.

these stones are set on a gravel base, then in leveling sand. they are irregular and what i'm planning on doing is dry sweeping mortar into the spaces between the stones, wetting it down, sponge wiping the stone to remove the mortar, and then just letting it dry. i'm pretty sure that the small spaces will dry up hard, but am wondering if the mortar in the larger spaces 2-4" will harden up or will remain soft. has anybody done this and what were the results?