Inquarted silver / gold Nitric Is Yellow/Brown, not Blue, HELP

[belmontclan]

I have 150g scrap 14k from all sorts of items, white gold, jewelry, dental etc.. but it acid tested 14k, I inquarted with .999 silver bullion at 200 grams and made shot out of it.

This is my first nitric 70% with 1 to 1 distilled water.

The color is yellow/brown instead of blue! Is this because of pmg’s and other impurities in the alloy? IS something wrong?

Will I be able to cement my silver out of this solution with copper?

Help!

Thanks.

 

[goldenchild]

The dental scrap and or white gold most likely had palldium in the alloy. This is why it's important to separate your different types of scrap to make things easier. You'll still be able to cement your silver but you'll also bring down Pd.

 

[Lino1406]

To me it looks like iron

 

[nickvc]

If you are sure you have Pd, test the solution, then add salt or Hcl to form silver chloride, filter off the solution and cement the Pd with copper.

 

[goldenchild]

To me it looks like iron

I thought the same thing at first but then realized that it was all alloyed. I don't think that could have easily been achieved with iron. I guess we would have had to see the shot before going into acid. The alloy looks ok in the first picture though.

 

[belmontclan]

Thanks for the help everyone, I'm almost certain its PD,

It appears ready for AR now its all brown and brittle.

I might try to salt out the silver then cement the PD, thanks for that IDEA!

Ill have to ready how to convert Silver chloride back to metallic though.

 

[kurtak]

Keep in mind that with white gold & dental gold in the mix besides Pd there is also likely to be Pt involved & "maybe" also Rh (as in white gold plated with Rh &/or a trace used in the dental - &/or for that matter Ir used in the dental alloy)

In other words "other" PGMs involved besides Pd

The point being --- where are those other PGMs going to end up ?

Pt --- depending on the ratio of Pt to Ag some of the Pt may dissolve with the nitric (when dissolving the silver) - or - none of the Pt will dissolve (with the nitric) - or - all the Pt may dissolve

Most likely - some - of the Pt will be in the silver nitrate - & "some" of the Pt will be in the gold (sponge) & for that matter there will likely be some/trace of Pd in the gold sponge

That means when you dissolve the gold sponge with AR the solution will also (likely) have Pt &/or Pd in it

If you use SMB to drop you gold from the AR it will likely drag "some" Pt/Pd down with the gold drop

Therefore I would use copperas to drop the gold as it will give you a "cleaner" gold drop (though you "may" still get "some" drag down of Pt/Pd

Rh - if any (Lou may have to correct me here) but I believe like Ag/Pt alloy - depending on amount in the gold sponge - some - none - or all may dissolve when you treat the gold sponge with AR

Ir - if any (again Lou may have to correct me here) but I believe most or none will dissolve in the AR treatment of the gold sponge - it "should" end up as a "fine" dust in the bottom of your beaker --- it will be ultra fine so give it time to settle

You will know if PGMs have "followed" your gold after you melt it - & after it has cooled - the button/bar will have a fern like pattern on the surface - & it only takes "traces" of PGMs for the fern pattern to show

bottom line - this is way we normally "try" to keep white gold &/or dental gold separate from other (normal) karate scrap --- PGMs alloyed with gold (&/or silver) makes the refining of the gold (or silver) more complicated

Kurt

 

[belmontclan]

Thanks Kurt that makes a lot of sense now,

Ive noticed its taking more washes in the nitric before it starts to get clearer,

Would you recommend to keep washing in the dillute nitric until its clear?

The gold sponge is brown and brittle but its still yellow in the washes...

Thanks a ton.