She now knows she's getting something, with the vaguest of ideas of what (metalworking/silversmithing was as much as I would let on), had to leave for the appt though before I could finish it, and in any case, the torch picked now to run out of gas. But the mould is filled and there are spare ingots of silver ready to be ladled in to fill the capacity left behind due to shrinkage, since with this polymer binding trick, you do get a bit of shrinkage due to the space taken up by the binder. But that just means I'll be there ready and waiting, keeping the heat on so the mold doesn't crack through thermal shock, keeping it blazing hot and standing by with a DIY-ed ladle, held in some long pliers, holding some additional molten silver to pour in and fill up the space taken. Did carve a bit of additional space too to account for losses, rather do over than under, that way I can take out a set of precision files to shape it exactly, smoothe off any imperfections with progressively finer grades of sandpaper, until its ready for electroplating in a PdCl2 solution (palladium chloride) Although I am contemplating a different approach, and using iridium tribromide instead. Because iridium metal is INCREDIBLY resistant to, well, pretty much everything short of an atom bomb:P
An acetylene torch won't melt it in the solid state, although as a plating that would melt the metal inside, not sure as such a thin surface layer would hold its shape, its incredibly resistant to chemical attack, and does not tarnish. It takes either fused molten cyanides, or molten caustic alkali metal hydroxides as fused melts to attack the stuff, second-highest melting point of any element IIRC, and it is VERY hard. Trying to file it after would doubtless just destroy the file, if it were anything but a diamond abrasive. But iridium metal also has another attraction than durability, whilst palladium is bright, with a warm, slightly golden and good looking (just like the lady its intended for
) color,, iridium also has a subtle, darker play of blue-grey-greenish iridescence to it in the right angles. Wouldn't come cheap, but I wouldn't mind buying a gram or two of IrBr3 or IrCl3, and using the rest for experimenting with iridium-based hydrogenation catalysts, and using it for plating onto other metals to serve as electrodes when electrolysing otherwise virulently corrosive materials. as well as plating onto crucibles for similar reasons, when the melt inside is going to be a pretty nasty customer to the container without a resistant layer on it. Solid Ir crucibles are available, but they do not come cheap at all.
But the indended recipient of this little, hopefully pretty, piece of jewellery, isn't going to know I paid anything of the sort or she'd go nuts at me probably
All in all, though I think that a relatively minor sin, compared to many I've comitted, am comitting, am going tol commit, enjoy comitting and have mentally noted down for comission in the future.