Mention was made in this necrothread to silver soldering.
There are low temperature silver solders - this is what is shown in the videos. Certainly clean useful material, but actually a soft solder not unlike traditional lead/tin solders. Maybe 4% silver.
There are high temperature silver solders. High silver content, red heat required. Akin to brazing. Much stronger than the soft solders being shown.
I have made restorations as shown sweating the joint with soft solder.
