GF watchbands

[qst42know]

That depends on the band.

 

[samuel-a]

Is that 1/20th of the weight of the caps or the whole watch band?

just the caps.

the rest of the band is SS or sterling and is also marked that way usually.

 

[brjook]

I have been stripping some GF watchbands in a sulfuric cell and it works great.When i have a GF stainless mesh band it seems to keep a high amperage and along time to strip.Does the cell also strip of the stainless and comtaminate my gold?

 

[goldsilverpro]

Is the solution turning green? This can happen if the stainless contains a lot of nickel. Once the dissolved nickel reaches a certain level, the sulfuric can stop working efficiently.

 

[brjook]

Can't tell if it is green or not the solution is black.I also noticed that the high amp long time peices are white gold and they use nickle to make white gold right.So in the long run when i get ready to process my gold powder what do i have look out for as far as nickle is concerned?

 

[goldsilverpro]

Can't tell if it is green or not the solution is black.I also noticed that the high amp long time peices are white gold and they use nickle to make white gold right.So in the long run when i get ready to process my gold powder what do i have look out for as far as nickle is concerned?

Nothing, really, but normal purification of the gold is necessary, whether it contains nickel or not.

 

[qst42know]

Be sure to test for palladium from white gold filled.

 

[Nickpearl]

I've recently joined and am learning tons.
One lesson: I used nitric to dissolve gold filled and had some of the caps (bottom and top) from the GF watch bands. Now I have stainless (bright tiny sparkles) in with my brown powder. Any ideas to get the stainless out?

As a note, from clean GF I extracted .5g AU from 35g of material. It tested better than 14K (at 18K solution (test kit) the streaks slowly faded but retained some form). I also extracted .25 grams AU from 135g of gold plated contacts.

Any comments on this post would be helpful.
Thanks. :roll:

 

[Harold_V]

I've recently joined and am learning tons.
One lesson: I used nitric to dissolve gold filled and had some of the caps (bottom and top) from the GF watch bands. Now I have stainless (bright tiny sparkles) in with my brown powder. Any ideas to get the stainless out?

That's not making a lot of sense. Nitric doesn't dissolve stainless, so unless you've done something beyond what you've said, there shouldn't be any particles present. Stainless would have retained its original form. I guess my first question is, did you dissolve the resulting gold, filter and precipitate, or are you speaking of the gold that resulted from dissolving the base metals, with no further treatment? Also, consider that it's possible you have dissolved something that is rhodium plated, which would result in the tiny particles you speak of.

Typically, you can look upon the first reaction (dissolving the base metals) as just a recovery procedure. While it's true that anything you do to increase the gold content can be looked upon as a form of refining, it's wise to make a distinction, so you understand that your work is not finished. Said another way, one recovers the values by various means, which are then further processed to enhance quality.

Assuming you haven't digested the recovered gold, the traces of impurities will be chiefly left behind when you do. They may go in to solution, but selective precipitation will recover the values, leaving behind the contaminants. That's assuming you use a selective precipitant. The resulting gold powder is then washed properly, to remove contaminants that are dragged down with the gold. To further purify the gold, raising quality to 9995 or better, the gold powder is then dissolved once again, and re-precipitated.

You may achieve some degree of success washing the material in question in dilute sulfuric, heated. In any event, a proper refining should eliminate the contaminants of which you speak.

Harold

 

[goldenchild]

I bet it's rhodium plating. If those sparkles are still there after digesting the gold foils then it is rhodium. Or something non metallic.

 

[Harold_V]

Or something non metallic.

One of the things I did, routinely, when I processed gold filled objects, was to eliminate base metals, then gather all of the remaining solids in a filter. They were then incinerated, a process that is chiefly ignored by the masses. There was method in my madness, and your comment helps cover my point.

Beyond eliminating non-metallic contaminants, incineration was useful in converting tin to an oxide. It wasn't uncommon to find gold filled objects that contained traces of soft solder. After incineration, the lot was screened, with a magnet used to eliminate any traces of magnetic materials, then the sifted solids were given a wash in hot HCl. A boil, actually. After proper rinsing, the solids were then dissolved in AR. This yields an incredibly clean solution that filters quite well. But then, as is usual, this is likely to fall on deaf ears once again.

Harold

 

[Nickpearl]

Thank you Harold and Goldenrod.
Your comments are right on.
I did filter the nitric solution, rinsed but mostly with water, then dissolved in AR.
I used the Hoke method of boiling down, adding some sulfuric, boiling down more and adding HCl, then rinsing (mostly decanting) until the final filter step.
The powder I've ended up with ranged from dark to lighter.
Here's what I found - tell me how I'm doing...
1. Definite final wash of the powder in HCL, heated. Rinse.
2. I do not know how to incinerate (filters or powder or anything) and all that powder stuck in filters was annoying, so this is what I now do.
After all is said and done, I pour the rinsed powder into a flat glass tray. I let it dry. I scrape it off into a melting tray (silica) with a bit of Borax and melt. Wow, did I get pretty gold.

Lastly, and this is my fault, I've used both processes to get powder - Nitric alone on gold-filled items (no AR) and those lots with AR.
Both only test on my acid stone at 14K to 18K.
I will next take your advice and re- AR a gram or two of my little buttons to try and improve the purity.

Thanks much again!
Nick

 

[Harold_V]

I used the Hoke method of boiling down,

Uhhh---Hoke does not have a method of "boiling down", and you should immediately stop using that term. It is a huge mistake and taken literally by those that don't understand what they are doing. One does *NOT* boil down. One evaporates. They are not the same thing.
I hope you accept this in the spirit in which it is offered. I fully expect you, and all other readers, to use PROPER terminology when posting---to prevent stupid things from being promoted.

Here's what I found - tell me how I'm doing...
1. Definite final wash of the powder in HCL, heated. Rinse.

If you washed only once, that's not adequate. Also, if your objective is high purity, gold should be re-refined. It becomes obvious why when you start doing so.

2. I do not know how to incinerate (filters or powder or anything) and all that powder stuck in filters was annoying,

What you need to do is read more. This subject has been well discussed on the forum.

Why you, or anyone, uses a filter once gold has been precipitated is something I don't understand. It's not necessary, and it creates more work, plus ties up a small percentage of the gold. Once you precipitate your gold, it has no reason to leave the vessel (I always used beakers) until it was time to either weigh, for settlement, or to melt. If you're adding any steps, you're wasting time, all for no gain.

so this is what I now do.
After all is said and done, I pour the rinsed powder into a flat glass tray. I let it dry. I scrape it off into a melting tray (silica) with a bit of Borax and melt. Wow, did I get pretty gold.

After pouring off the rinse water, leave the gold in the beaker, which is heated at a low heat until all the remaining water has been expelled. During that process, you should shake it around a little to prevent the powder from sticking. Heat slowly, to prevent steam explosions, which lead to lost gold. Once dry, elevate heat, to expel residual acid (yeah, I know--you rinsed it out. Well, friend, you didn't. Do as I say and you'll see evidence I'm right).

Wise people do NOT use free borax when melting gold powder. For starters, it's not necessary, plus it is the source of lost gold. If you melt gold mixed with borax, a small percentage will remain in the slag, and it's not easy to recover. Instead, pour your gold powder to a dish that has been properly seasoned and coated lightly with borax. Heat it carefully, so you don't blow any of the gold out of the dish. Once it crusts over (with molten gold) you can increase heat. When it has all melted, it does no harm to sprinkle a few grains of borax on the molten button, which will help absorb oxidized contaminants. If you melt under a full flux cover, contaminants will not oxidize, and will not be removed by the flux. The button may look good, but it is still contaminated.

If, when you get your gold molten, you see a hazy surface, originating from the center of you button and moving towards the edges, that's a sure sign your gold is not pure. Pure gold will melt without a haze, and has a greenish yellow luminescence, with a bright surface. It will not discolor the flux, aside from, maybe, leaving behind traces of pink through purple---which is nothing more than colloidal gold. If the flux in your dish, after melting, has any color beyond that which has been described, your gold is NOT pure.

Lastly, and this is my fault, I've used both processes to get powder - Nitric alone on gold-filled items (no AR) and those lots with AR.
Both only test on my acid stone at 14K to 18K.

Ok, here's something for you to ponder. A touch stone isn't really well suited to judge gold purity, not for refined gold. You're looking for such small percentages that it simply can't make the distinction.

Depending on your objective, it is a mistake to process by nitric alone, especially gold filled objects. They have the potential to contain tin and lead, along with the alloying elements. Unless you give the resulting gold a hard, prolonged boil, you are not likely to remove the alloying elements to any meaningful degree, and if they're 14k or greater, maybe not at all. Such material should be boiled hard in nitric, then given a rinse to separate the base metal solution from the solids. With the solids in a filter, incineration is a really good idea. That can be accomplished in an old stainless fry pan, heated from below with a gas burner. Once fully incinerated, the solids are then given a boil in HCl, which eliminates tin (commonly found in gold filled materials). That makes the resulting gold chloride solution easier to filter, and helps tremendously with quality. After rinsing well, the material is then digested in the solvent of your choosing (AR, for example).

I do not endorse, and, in fact, discourage, any direct processing in AR. Base metals should always be removed first. If you don't do so, you risk loss by cementation, plus the resulting gold is typically very dirty. It's a judgment call---didn't say it doesn't work--it does. It's just not a good idea.

Read Hoke.

Harold

 

[Nickpearl]

Harold, I'm getting there. I'll take this 2.6g from 77.7 gf batch and wash in hcl to clean.
Later, I'll also post a pic from a previous batch where I ended up with lot's of silvery mud in the nitric stage.
I did re-AR 3.1g of previous AR'd Au and ended up with 2.5g of nicer gold with waste consisting of a tan-colored powder.
I also got .3g Au from a couple boxes of gold-rimmed wine glasses.
I trust I'm on a role, and yes, I re-read Hoke, the handbook and this site......
Comments?

 

[Nickpearl]

Harold?
Where on this post can I find instructions on incineration.
I have plenty of these chips (pic) and plenty of filters i need to reclaim the gold from.
Thanks for you help.
Nick

 

[Nickpearl]

This is the powder I melted to the 2.6g Au two posts ago.......

 

[Barren Realms 007]

That is a tough looking button, I would say there are some impurities in there. I'm a little concerned when you said some of the trash had a tan colored powder, there might have been value in this.

The flat packs you can incinerates to temps above 700 F and run your tourch over the material till there is no more glowing of embers from the material, then crush up the material to a fine powder and run in your favorite process.

The powder looks pretty good.

 

[Nickpearl]

Thank you, Barron.
I saved the filter with the tanish-residue from AR-ing the karated gold. I'll look at it again.
Thanks for the incineration tip.
The button does I think have some roughness to it, not sure why. I have heard re-AR'ing even "pure" gold is suggested - I'm sure I will since I have so much fun doing it.
Again, thanks!

 

[Harold_V]

Barren covered incineration pretty well. I used to use an old stainless fry pan, heated from below, then adding heat from a large torch at the end. Worked for me, although a little labor intensive. Adequate for small amounts, for sure.

I agree with Barren's comments----the gold doesn't look pure, although quite close. Surface is slightly discolored (assuming color balance is right with my monitor) and the less than shiny finish speaks volumes. When gold has a frosty appearance, it's usually because of traces of base metals.

Lead can be a problem. Make sure you use a few drops of sulfuric acid in the final stages, before filtration.

Also, washing is best accomplished in repeated cycles, with an ammonium hydroxide wash included. It will remove traces of silver chloride that may not, otherwise, get removed.

Looking good, so don't get down over these comments. It won't be long until you're producing high quality gold.

Harold

 

[Nickpearl]

Thanks, Harold, you and Barron's comments are well appreciated.
A question on ammonia.
How much household ammonia do I use to wash?

Thus far, after AR, I decant with water several times.
Then I HCL
Rinse some more.
I would assume I drop in as much ammonia in one of these washes as I did with HCL (in my case, for the 2.6g button, I used maybe 2-3 ml).

After the ammonia wash, I would expect to rinse repeatedly (under heating pad heat), stirring. By then, of course, the gold is starting to clump.
~~ Do I then crush the clumps to make sure it's rinsed or just stir?~~

Lastly, should my last two rinses be with distilled water?

Again, thanks, and although I'm not sure where you live, I live in Minnesota and it's getting cold. I'm thinking of traveling to a friend's in Arizona and rent a jackass and a sledgehammer to see if I can find gold near Wickenburg (kinda joking, kinda not).