After the Spirit Ascension
Those Old Classic Spirit stone no longer work on my test. New one is Spirit Stone.
Spirit Stones can be obtained by refining Ancient Spirit Fossils at Edern.
Old and new Ancient Spirit Fossil will work on Edern.
Thanks. It may be good to put it on the page for future/older players who have this confusion. It's good to know, and definitely simplifies the process of creating and transferring spirit weapons.