Granulation

Granulation is the process of joining tiny balls of precious metal to a surface.

When a tiny piece of silver or gold is heated to melting point with a tip of a blow torch the metal pulls itself into a perfectly round ball. I remember this as magical thing to do as a child, playing with scraps of silver and copper in my grandmother's workshop.

These grains or shot are called 'raindrops' in Native American metalwork.