While I can't answer the 24k to 22k question (my guess has to do
with the softness of 24k), I can tell you that 22k can be fused to
fine silver as I've done it. It's very tricky and if you overheat it
you risk plating your gold silver. If you're using silver granuals,
fuse them first then fuse the gold last. I fused them using the same
method as I did for all 22k and all fine silver - using the hide
glue-copper hydroxide mixture.
I have not found a book on the subject, but am as interested as you
in finding one. I do mine granulation by trial and error. If I mess
up the surface surrounding the granuals, then I just cover it with
Good luck and feel free to contact me offline if you want to discuss
granulation further. I love doing it!
Red Bee Designs