I’m relatively new to working with platinum and I’ve run into a
problem that I hope someone can help me with. I had some scrap
platinum that I tried to melt into an ingot. The way I was shown to
do this was, on the back of an old crucible, melt the pieces and as
they melt move the metal around with the force of the flame so the
pieces form together into a solid piece that can then be hammered
into a shape that can be sized on a rolling mill. This method was
demonstrated to me and I did it myself a while ago. I went to melt
the scraps today but mistakenly used the concave side of a crucible
that had flux in it. Before I went too far I was able to get the
platinum out of the crucible but some of the pieces got flux on them.
I didn’t think that would have much of an impact so I then started
melting the platinum the way I was shown, on the back of a crucible.
The melting was going fairly well and most of the platinum was melted
together but I was interrupted before I finished and I had to stop.
When I came back to finish melting and forming the melted shape, the
platinum was fairly well imbedded into the back of the crucible with
some amount of flux around the metal. I tried to continue melting but
I just couldn’t get the platinum I had just melted to melt again. The
flux melted but the platinum wouldn’t budge and I now can’t get the
platinum off the back of the crucible. I realize that I shouldn’t use
flux with platinum and the flux that is there was from my using the
wrong crucible. I was surprised that I couldn’t get the platinum to
melt again. The torch I was using is very hot and used many times for
melting platinum. Did I contaminate or alter the metal to raise its
melting point? Any ideas how to get the metal off the crucible,
preferably with out breaking the crucible?
Thanks for indulging a novice,
Larry.