I have a question regarding the use of pumice blocks for soldering.
I live in a small coastal town in Venezuela and often cannot easily
get the bench supplies and materials that I need. For example,
Charcoal soldering blocks. they don’t use them here, or at least I
have been unable to find them. I normally use a white soldering
board, however my current project, a filigreed Paua shell brooch
needs something I can press into (like charcoal). I have found a
pretty porous block of Pumice down at the local Chinese emporium. It
looks as though it will do but I would like to know if the pumice or
embedded mica chips will affect the integrity of the welds or
anything else. I would appreciate any comments or feedback on using
pumice in this way.