Hi! I'm wondering how one could apply tiny granules onto a
hollow fabricated ring (sterling silver, all seams hard
Have you considered classical granulation techniques? While the
temps required would be above the hard solder flow points, if
your seams are cleanly done, they won’t actually collapse any
more than they did when you first soldered them. Classical
granulation is done by copper plating the grains (soak em in
very used pickle, or new pickle with copper sulphate added, in
contact with some iron.). once copper plated, glue them in place
with a quite dilute mix of hide glue and a very little batterns
flux. Gently heat the result after tha glue dries. The glue
carbonizes, keeping the copper clean during heating by creating
a reducing atmosphere. The contact between the copper and silver
melts at the eutectic point for copper and silver, and when that
happens, the plated on copper briefly flushes, with the surface
looking momentarily wet and molten, like running solder. As the
copper then diffuses into the silver, The surface freezes again.
In the process though, the grains adhered/fused themselves to
the base piece, without themselves ever being hot enough to be
melting. This is easier to do if the actual grains are made of
fine silver, even if the base piece is sterling.
Quite a number of currently available books detail the process.
I like John Cogswell’s description in Tim McCreights “Metals
Hope this helps.