Pt and Au

[VanMarco]

Hello guys

I start knowing that I haven't done my homework in full, so I apologize for that. I'm a real fan of this forum and I read alot of posts.
Basically, I have put about 3 oz of silver scrap (925) jewellerly in nitric acid. Now, I have bought this for cheap, and I hadn't
bothered to test it as if there were other PM in the lot, sure thing 99% had a 925 halmark on it.
Now, upon dissolution in nitric acid, a couple of bracelets did not dissolve not even heating.
One turned out to be gold, and another silvery metal also did not dissolve, my guess is platinum, but I could be wrong
by not doing my homework and testing every single piece thats what I ended up with.
Now I have the copper/silver nitrate solution filtered and ready to precipitate, and the issue is not that.
All that was left on the bottom of the flask, the chains that did not dissolve, plus I've got a fair bit of brown/reddish dust.
I suspect that is gold as well, as I have removed all the springs into the connectors and also I have heated the items with a torch before putting them in to be sure no coating or dirt/grease was left.

Now my question is, how do I go to recover both the Pt and Au, my only idea is to wash the stuff thorougly and then add aqua regia, but the question I have come up with is, if I do dissolve both Pt and Au in aqua regia, then if I use SMB for the gold, of Ammonium chloride for the PT, in both cases I suspect that both metals will precipitate out at once, or I'm wrong

Thanks and sorry for the long winded post, I will also post pics as soon as I can

 

[Justincase]

Mistaken Au for Ag which you got for a reduced price lucky man. I hope you might consider passing some of your good fortune back whens it came.
As for the silver colour metal that would not dissolve, Pt is only one option and would lightly be well marked if it was a P.G.M. but you should make sure as the intrinsic value of such a piece would be quite good.
but Stainless Steel would not dissolve either and is much more popular to wear now a day's.
In any case the practicality of your position means you should put it all to one side until you have attended the Hoke School for six months to a year before going forward.
If you wanted a quicker return of your capital it might be best to pass on your solid's if not the hole lot to some one who is already operating.

 

[nickvc]

The silvery coloured bracelet could be white gold and if it is it's likely to be 14 or 18 k but as Justin pointed out it's also possible it's stainless, my advice is to test that piece and if it turns out to be gold then you may need to inquart before dissolving all the remaining material in AR, make sure you test all your solutions for PGMs before safe disposal. Good find they don't come often.