That is a really cool thing to find out. i mean he could maje a weeks worth of spirit stones and change them for a months worth of monster cores! Talk about cultivation resorces
... depending on benefits of spirit stones vs cultivation I can see this going two ways 1. make them in real world to speed up his cultivation or 2. make them in real world to increase his allies cultivation in the ?mortal world?(not sure what the technically realm name for earth is)