I can't find anything in the manual regarding this. I know that certain stone combinations will create different spells, so I'm wondering if I need to adjust my current "strategy" of just running around and picking up whatever stones are lying on the ground, or if there's a way to arrange them after the fact. If there's not, then I'll know I need to be more picky about what stones I pick up when.
If you hold a charge for a spell for too long, you will drop all of the stones that you are currently holding for that spell. If you do this in sequence with all of your stones, you can reorder them entirely by then picking them up in the correct order.
It only takes a few seconds so it generally doesn't take too long, but it is still yet faster to prioritize your stone collection a few steps in advance.