FWIW, the artifacts from King Tut's tomb include many superb examples of "Granulation" -- which, I understand, depends on the fact that tiny spheres and wires of gold can be bonded (welded) together using only heat and pressure (no solder required).
FYI, the same ("thermocompression bonding") principle was, for many years, the sole means of bonding gold wires between integrated circuits and the packages that connected them to "the outside world"...
Facinating.