Separation of metals from alloy consisting of gold, silver, copper and palladium

Gold Refining Forum

Help Support Gold Refining Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

snoman701

Well-known member
Joined
Oct 8, 2016
Messages
2,108
Location
SE MI
If I have say, an ounce of the above, with individual metals mixed at a 1:1:1:1 ratio, will I be able to recover the palladium back to a purity clean enough to use in jewelry? My concern is mostly the quantity, and the ease of the learning curve on refining. It is often said that the PGM's aren't easy to do refine in small quantities.

Please note that I have NOT read up on PGM's much at all, so I'm very green. I'm trying to decide if I should dedicate some time to reading up on them, or just dedicate the time to silver and gold technique development.

I've dreamt of working with Mokume Gane since I first saw it in a jewelry shop. If I can refine out my own learning curve, then it's entirely within my grasps...but as we know, the PGM's do not refine inexpensively. If I have to pay a 10% surcharge to buy the sheet, then 20% to have them refined...it's just not something I can afford to do, especially when the STEEP learning curve will have me trashing a lot of alloy just to get to the point that I can join them consistently.
 
I don't see the separation of the metals as the hard part. To melt and make a nice palladium plate has to be the hardest part.

To separate palladium from the other metals is not hard. The easy way out is using DMG. It is to separate the various platinum group metals from each other that is a craft.

As it is basically inquarted at those proportions, I would dissolve copper, silver and palladium in nitric acid. Gold pure enough to make new alloys is left behind.

The silver can then be extracted with chloride ions and filtered off, then there are a number of alternatives to precipitate the palladium while leaving copper in solution. This could be a bit tricky but it is possible to do if researched well and care is taken while doing the procedure.

Alternatively the palladium could be extracted with DMG, ignited and melted down. The silver can be cemented on copper, leaving copper in solution.
Using DMG would probably cost you a dollar or two per recovered gram of Pd but it is an easy way to do it.

Göran
 
g_axelsson said:
I don't see the separation of the metals as the hard part. To melt and make a nice palladium plate has to be the hardest part.

Göran


Resounding yes to the above comment.
 
Why not wait on the palladium for now, and work with the layers in silver-copper-silver-gold repeat as needed until the desired thickness. (Since silver and palladium are fairly close to the same color.) Then you could make the jewelry and show it off here so we can all see it. I really like the way Mokume Gane looks, it makes some very beautiful patterns and jewelry.
 
Lou said:
g_axelsson said:
I don't see the separation of the metals as the hard part. To melt and make a nice palladium plate has to be the hardest part.

Göran


Resounding yes to the above comment.

I thought palladium could be melted via TIG welder set up as a plasma arc furnace, of course, with appropriate crucible. If I can get it to a button, I can roll it out.

I know that there is at least one "button melter" out there that uses a water cooled copper crucible and TIG welding power supply. Though I admit, I am curious how one would contain the melt with just a water cooled copper crucible.

There is also a ganoskin video where Steve Lindsey melts palladium scraps with tig torch on a titanium diboride sheet.

Unfortunately, the induction method is out, as it's too high of a frequency. If I could get away with an old Lepel brazing power supply, I'd go for it...but IIRC, that's only 70khz.
 
While it can be melted with a tig torch, I think I'll just skip the PGM alloys. I don't want platinosis, or to even expose myself to that crap.
 
Lou said:
It's an arc melter you speak of and yes Pd can be melted in it.

Does this make a dense, workable Pd button? My understanding is that they use a water cooled copper crucible/hearth.

For everyone else, here's one example.

http://www.cianflone.com/products/lab-sample-preparation-equipment/electric-arc-button-remelt-furnace/

Here's another, where the crucible is clearly seen.

http://mrf-furnaces.com/products/arc-melting-furnaces/arc-melt-furnace-sa-200/

Here's the video by Steve Lindsey. He uses a high temperature conductive ceramic to remelt 950 TruPd, which he then uses as filler wire for resizing palladium rings.

https://www.ganoksin.com/video/palladium-melt/
 
Interesting video but one concern is contamination by the titanium diboride. Look at the surface tension of the Pd--it's not forming a round button and that wetting action is concerning.
 
I'm actually taking a Mokume Gane class next month--whee!

That being said, I'd probably do palladium & PGMs like I'm currently doing: cement them out and collect enough to have refined. I pick and choose when I'm doing jewelry from raw materials, and mokume is not going to be one of those things. I'll just buy the pre-made billets and sheets (probably from Reactive Metals and/or a GRF member), texture them myself, and feed a "contains Pd" scrap jar when I'm working with Pd stock. I'll dodge the Pd by either using a chloride method to drop the silver, or just know I'm cementing Ag/Pd after nitric and electro-refine it, saving the slimes.

Now that I've "talked" through it (while subjecting you all to my thought process), I'll probably just skip the Pd jar and process all my scrap at once, ensuring a lower percentage of Pd in my silver cement.
 
upcyclist said:
I'm actually taking a Mokume Gane class next month--whee!

That being said, I'd probably do palladium & PGMs like I'm currently doing: cement them out and collect enough to have refined. I pick and choose when I'm doing jewelry from raw materials, and mokume is not going to be one of those things. I'll just buy the pre-made billets and sheets (probably from Reactive Metals and/or a GRF member), texture them myself, and feed a "contains Pd" scrap jar when I'm working with Pd stock. I'll dodge the Pd by either using a chloride method to drop the silver, or just know I'm cementing Ag/Pd after nitric and electro-refine it, saving the slimes.

Now that I've "talked" through it (while subjecting you all to my thought process), I'll probably just skip the Pd jar and process all my scrap at once, ensuring a lower percentage of Pd in my silver cement.

So what's the class for if you just buy billet? Developing the patterns? Do you have a roller, or will you be forging everything? I like the compound patterns the most. You forge it out, then cut it up, then forge weld it all back together.

I fell in love with it when my sister in law worked for a jeweler, they had damascus pocket knives...and I told the jeweler they were awesome. At the time I was an art major and he pulled a piece of mokume out of the safe. That must have been 15 years ago.

I used to have the Ferguson book...thus far I have went through my storage unit (twenty milk crates full of notebook sized books)...as well as my old apartment (at the inlaws house...more books) and all of the books I have at this house. I can't find it, but I DON'T want to pay the current asking price. I did manage to find the hydraulic die forming book that I was looking five years ago though. Soooo many books.
 
Yup, it's a class on working with the billets and creating patterns (and I'm sure any special hints for working with the material). We have a nice Durston roller, but we don't have a press, forge, or furnace as far as bonding the layers to make billets. A pair of fiber kilns is about as close as we get ;)
 
upcyclist said:
Yup, it's a class on working with the billets and creating patterns (and I'm sure any special hints for working with the material). We have a nice Durston roller, but we don't have a press, forge, or furnace as far as bonding the layers to make billets. A pair of fiber kilns is about as close as we get ;)

Very cool...is the class ran through a local guild or something? I really should start going to the art center again, but my last experience was that it was me, and a bunch of soccer moms. At the time, I was in my early twenties...knowing what I know now, I don't think my wife would appreciate it much.
 
snoman701 said:
Very cool...is the class ran through a local guild or something? I really should start going to the art center again, but my last experience was that it was me, and a bunch of soccer moms. At the time, I was in my early twenties...knowing what I know now, I don't think my wife would appreciate it much.
Haha. Yes, it's a local guild (Patuxent Lapidary Guild). I'm the primary faceting & lost-wax casting instructor, one of the shop supervisors, and [stt]sucker[/stt] President, actually. And the guild is the reason I'm here at GRF--our landlord had a bunch of nasty old plating chemicals in the basement that we rent, and I wanted to figure out how to properly dispose of them, and possibly reclaim any leftover gold to cover costs. The latter part didn't work out, but I'm hooked haha.

I'm definitely in the younger half of the guild (at 47), so not many fetching soccer moms, but it's a fun place. I mostly go to a) reserve some time for crafting every week, and 2) hang out and see what other people are doing. The social & learning aspects are a big draw for me.
 
Back
Top