Slip Paste vs Solder?

by Kate.
(United States)

Will silver slip paste and a torch work well enough for joining small pieces of sheet metal and/or PMC or bezel-set cabuchons, or do I really need to invest in /learn how to use a soldering iron first thing?

Also, have been trying to find a comparable slip paste for copper and am not having much luck.

Is it called something else?

Kate