I was thinking that you should be able to fuse gems to get other
gems. Like x100 of dark gems for x1 of a dragon gem. Or fusing any
gems you chose to get a random gem. This is so that we can do the
gem cauldron and have an easier time completing the raylong quest.
For the example you've put, i don't see this like a "fusion" of
gems.
is more like exchanging gems, and we already have a gem
exchange Here.
So, no support.