This has really been my new go to flux!!  It works especially well for pressed flower art as you do not need to clean with soap & water.  I hope you enjoy using it as much as I do!
An all purpose, soft soldering paste flux.
Features: 
- Cleans and fluxes in one operation
- Flocks smoothly into any size cavity
- Works with 95/5, 60/40, 50/50, and 40/60 solders
- Odorless, non-agressive, & no affect on mirrors
- Cleans up with water
- Oil base protects solder joints from corrosion
Works With: Copper, lead, tinned steel, solder, & other metals