More important than the 'melting' temperature of your solder is the
'flow' point which may be as much as another 100 deg or more above
the former. That is the point the solder actually does its work.
That is why when students begin soldering they have this persistant
problem of the solder balling up (melting) but it just sits there and
never flows. Usual problem when doing silver is the heat is poorly
distributed though there may be other reasons as dirt, oxidation,
etc, etc. With gold, it normally not the heat but more than likely
one of the other 'mistakes'.
That is why the pencil torches cannot be used on any large pieces.
Fine for posts, jump rings, even a sizing, but don't expect to
solder bezels onto large back plates etc. The heat cannot be evenly
distributed and sustained.
Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut1