Purifying issues

[Skieferins]

I am having a bad run with reclaimed Silver at the moment...It just keeps having impurities as I cast bars.

The last thing I melted was an old 1890's Assay Hallmarked 925 gravy boat with solid feet, however no matter how many times I melt/remelt ,the Silver has porosity and is pitted.

I tried adding half a pinch of Borax instead of a pinch, I tried adding a fingertip sized piece of wood, I tried melted on a charcoal block first then in a crucible but the same results keep happening.

The last time I had this much trouble was when I used 700 Mexican Silver, which I ended up throwing in the scrap pile...Any ideas on how to purify it ?

Thanks :-)

[Gemsetterchris]

The last thing I melted was an old 1890's Assay Hallmarked 925 gravy boat with solid feet

Was that a good idea? :eek:

[metalsmith]

I am having a bad run with reclaimed Silver at the moment...the last thing I melted was an old 1890's Assay Hallmarked 925 gravy boat with solid feet

:-O I just hope the bar is even half as valuable as the gravy boat was and presently your not doing a ...#-o

[Skieferins]

The gravy boat was knackered beyond repair...Some knobhead who had it before we got it for scrap had mangled the poor thing to the point that it more resembled a silver yumyum cake...only a cake that had 3 feet sticking out and a twisted handle...By reclaiming it, I was probably giving the poor thing some dignity back ! LOL

[ps_bond]

Did you check for solder before melting it?

[Gemsetterchris]

Did you check for solder before melting it?

More likely that had it been nicked, can't think of any other good reason to mangle a gravy pot unless the gravy was that bad.

[Skieferins]

Nothing personal here Chris, but after looking at your unasked for self promoting link, its obvious that you have a lot of talent and experience...When I have your level of knowledge, I might start offering my views to help people who ask questions on this forum. But as yet, on this posting at least, I yet to see anything other that a veiled sneer at my inexperienced question.

Peter, I have never been told to nor how to check for solder when melting and recasting,I have always just melted up and recast...I've had around 80% success rate ending up with great cast bars. I've made around 50 rings from these but as I say these last few batches of silver have caused me real problems.

Just to explain, I have been learning since January and I am learning on a 3 day a week basis from a really talented near 70 year old highly skilled craftsman but as you might appriciate, he works using techniques that were taught to him around 55 years ago.

If there are basic questions that I ask, then yes they are questions of a totally green learner but weren't we all here at one point ?

[Goldsmith]

If you melt an item that is hallmarked, there is no guarantee that the melt bar will be usable silver. As Peter mentioned about checking for solder, if you melt an item that has solder on it the solder content will change the silver alloy. For casting purposes I know that those companies who cast from old silver will add some fine silver to the old silver to bring up the actual silver content and make it flow better. I myself would never bother to use reclaimed silver when making new items, I would sell the old silver and buy new with the proceeds. And I will add that next year I will be a 70 year old craftsman also.

James

[Skieferins]

Thank you for a straightforward answer James, I'll give that a go and see how things turn out. I'm taking it that I'll only need to add a small piece of pure silver to compensate for the solder ?

[metalsmith]

Don't be too sensitive. If the gravy boat was mangled, then yes, the bar will be at least half as valuable, but as Chris suggests, I would have concerns about the source.

The other guys have more experience than 5 or 10 of me; but I wonder if in heating it - you don't mention your method - but if you are torch heating, whether or not the lighter parts of the solder (generally brass-alloy, I understand) are not vapourising in the melt and hence giving this pitting / porosity you describe. Melts I do understand.

[Gemsetterchris]

but as Chris suggests, I would have concerns about the source.


Ask no questions, hear no lies :D

I've seen it all before, anyway It's irrelevant to the original query..what James was suggesting is that you sell the scrap & buy new material so as not to waste your time, which may or may not work.
That is unless you happen to be more interested in melting down a sackload of silverware rather than making jewellery..?

Thanks for clicking the link you didn't want by the way.:)

[Gemsetterchris]

You will also find that a useless piece of scrap that is hallmarked will net a fraction more cash than a pitted blob that weighs the same (which is what metalsmith was pointing out)..hope you find some help in that.
Up to you & best of luck.