Yields correct?

Shop deals on ebay
xelexo
Advertise with us
shop deals on amazon
Gold Refining Forum

Help Support Gold Refining Forum:

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

takenbyvultures

Active member
Joined
Dec 4, 2011
Messages
29
I ran my second batch this week and was hoping to get a "form check" for my yield. I started with exactly 2lbs of close-cut PCI card fingers, used 2:1 AP method with agitator, 4:1 HCl/Cl, SMB drop, 24 hour wait, Stannous Test, and the powder came out to 2.1g, once it was melted i got a total weight of 1.9g, does this seem right for 2lbs of close-cuts? In the photos, the larger button is one I'm referring to, the smaller one was from a test run a few weeks ago.
Thank you.
IMG_20120807_173030.jpg

IMG_20120803_163013.jpg
 
I usually average about 2 grams per lb. That seems to be a safe goal to shoot for.
Maybe a bunch of partially fingered, or lightly gold plated cheapie fingers may give you lower numbers.
There are some I don't bother cutting off if the color isn't right.

Jim
 
Thank you for your response, I picked through all of the fingers and picked out any that were off-color and a few were silver(tin?). Could 24 hours not be enough for the gold to settle? I used stannous and got a light brown reaction which appeared to be traces of platinum, could this have been a false positive? The filter i used to strain the solution has only very light signs of powder, nothing that would effect the end weight really.
 
takenbyvultures said:
Thank you for your response, I picked through all of the fingers and picked out any that were off-color and a few were silver(tin?). Could 24 hours not be enough for the gold to settle? I used stannous and got a light brown reaction which appeared to be traces of platinum, could this have been a false positive? The filter i used to strain the solution has only very light signs of powder, nothing that would effect the end weight really.
Click to expand...


Was the 24 hour wait before you used smb to precipitate or after?
In your first post you said "4:1 HCl/Cl, SMB drop, 24 hour wait, Stannous Test, and the powder came out to 2.1g"

Jim
 
takenbyvultures said:
I used SMB then left it overnight, the next day i used stannous to test.
Click to expand...

You are supposed to let it sit for about 24 hours to let the chlorine dissipate, then use smb.
You may still have gold in solution because of that.

Jim
 
I just precipitated this batch a few minutes ago. 95% of the gold hit bottom within 3 minutes. I'll let it sit overnite & finish rinsing in the morning. I'll stannous test, but I'm pretty sure that all the gold dropped. My guesstimate, 2 to 3 g of gold.

Take care!
Phil
 

Attachments

  • e-scrap 032.JPG
    e-scrap 032.JPG
    86.4 KB
Great info, thank you! Jimdoc, I only waited maybe 20 minutes from the point when i mixed HCl/Cl and dropped the SMB, so that could very well be the problem. So mix HCl/Cl and leave for 24 hours, then drop SMB and wait how long? Philddreamer, I saw the same results, after SMB drop the first few minutes showed approximately 95% settled. How many lbs of fingers did you start with?
 
It says 1# - 15 oz.
I just used the "pound" abbreviation. :mrgreen:

Taken, I processed 1 pound 15 oz of fingers. You don't need to wait 24 hrs in order to get rid of the clorox; just heat the solution and the clorox will be gone in a few minutes.
 
i agree. drive the chlorine out of solution using heat. i normally yield 2g per 1lb of fingers. you may have left some of your gold in one of your processes.
 
Finger yields can range from less than a gram per pound to upwards of three grams or more per pound for some fingers.

I've run many batches of mixed grade fingers and the yields were in the 1.25 to 1.5 gram per pound range. I've also run 'high grade' batches that yielded over three grams per pound. Two grams per pound is a good average, but nothing is certain with escrap. The worst 'fingers' I've ever processed were what appeared to be solid plating across the surface of both sides of the finger (imagine several pounds of communication board edges the size of normal fingers). Yields were less than 0.1 gram per pound.

Many factors including finger wear, plating thickness, board thickness, how closely they are trimmed, miscellaneous components on the fingers, batch losses, etc. can affect the final yields. Test all of your spent solutions and use your AP to saturation (dark bown color) to be sure no gold is lost in the solution. A copper saturated AP solution can take a long time to settle out all of the fine gold particles that are suspended in the thick solution. If you have the time and patience you can speed the settling with vaccum filtration. Finger solutions are notorious for clogging filter papers in the buchner.

Steve
 
Thank you so much for all of the help, I'm taking plenty of notes. After using heat to remove chlorine from HCl/Cl, what is the acceptable amount of time to let the solution settle before adding SMB? A basic hot plate should be enough to heat the solution, correct? The next batch I was planning on processing 10lbs, but I may hold off until I get the process down well, just so I don't lose any gold because of errors in my methods.
 
When I use heat to drive off the chlorine, I usually put a few ice cubes in another container and slowly filter the warm, not hot, hcl/cl into the vessel with the ice. The ice will chill your solution and dilute it at the same time. I find that a chilled solution precipitates faster and more thoroughly.



Edit. This is the way Harold V taught me to prep my solution for precipitation. Thank you Harold!
 
The filtering should be done after the addition of ice. Ice will lower the temperature of the solution causing less soluble salts of silver chloride and others to precipitate out. These will then be trapped in the same solution your clean gold is fixing to precipitate out in if not.
 
Palladium said:
The filtering should be done after the addition of ice. Ice will lower the temperature of the solution causing less soluble salts of silver chloride and others to precipitate out. These will then be trapped in the same solution your clean gold is fixing to precipitate out in if not.
Click to expand...


Thank you palladium for the correction. I was thinking about what I most commonly run, pins. The foils from the type of pins I run have no silver and have never been soldered. I should have clarified, because many of the things we process can have all kinds of different metals in solution. For example, ceramic cpus. The last batch I ran had nearly as much silver as the gold I recovered.

Sorry for the mistake.
 
If I'm not mistaken, Harold used SO2 gas to precipitate and added the ice to counter the heat generated by the precipitation reaction. Ice can also be used prior to preciptation as Ralph mentions to remove traces of silver chloride ( so both statements above are correct, but for different reasons). Cold solutions also hold more gas than hot ones.

I will go out on a limb and also state that Harold would also disagree with advising anyone to perform their reactions or processes based upon a set timeline for completion. Various factors affect how long a given process will take and each reaction will have different variables. Refining is not baking a cake, it is not simply add A + B to get C and bake for 20 minutes. One must make observations along the way and determine the endpoints of one reaction and proceed to the next. That said, as a rule of thumb very pure gold typically settles very fast, while dirty or colloidial gold settles very slowly.

Note to Harold, please don't think I'm trying to put words in you mouth, I simply feel I know you well enough from the things you have taught here, that I could make the above statement about your view. :p Of course, your feedback is always welcome!

Steve
 
tek4g63 said:
... For example, ceramic cpus. The last batch I ran had nearly as much silver as the gold I recovered...
Click to expand...

That is very typical of ceramic cpus.

Steve
 
Something has to be off by quite a bit considering I'm getting approximately 1g gold per lb of fingers, which is roughly $57 in gold per lb of fingers, but board sort pays $72 per lb on fingers. How would they make money on these, I don't think any silver or platinum would make up for the difference to break even. :?:
 
I think it's the law of averages in the case of Boardsort.

As Steve said, the yield can vary greatly, depending on the source, and also on how close they are cut.

I average about 2 grams per pound but my batches include a lot of fingers from ISA cards and slot processors.

A batch from mostly PCI cards may be lower since they're newer and, most likely, more thinly plated. You may have some gold in the form of powder in the bottom of the bucket you processed them in. Some may be in solution if it's not yet saturated with copper.

This could likely be the case especially if it's your first batch in this solution.
 

Latest posts

Back
Top