very low yields on pins

[steyr223]

Hello everyone
I have been doing a process on some pins with 42 percent nitric acid mixed 50/50 with water and stainless steel pot
I then decant through 3 coffee filters ,collect all my foils, and water wash till clear
Next I put my foils in hcl/ bleach
And filter to a charmin plug in a funnle
at this point I throw. In one of my my nuggets let it sit for a while and drop with stump out from Home Depot
I'm getting a half a gram per pound, Seems low to me I'll post some pictures tomorrow
thanks

 

[Geo]

you are testing all your solutions,right?

 

[steyr223]

Hey geo I'm sorry
that should have been
the first thing out of my mouth
of course I am ,in fact i made a spray bottle so I can spray it on a napkin and then put my solution o n top of it
I do have a little solution with a very small amount of brown powders that I still have to melt
Very little
I get a lite to dark brown color,nothing close to the deep purple or black.
I have asked many if they see even a faint purple
Some pics
thanks steyr223 rob

 

[butcher]

how many pounds of pins did you process?

 

[steyr223]

Hi butcher
1rst time 1lb+, used 1000 ml beaker many small reactions dropped beaker. Yield -.85 grams

2nd time 1½-1¾llb, used a stainless steel pot placed in a igloo
Water cooler in case of overflow.
I believe when it overflowed the exothermic reaction fused some of my foils to the plastic
Not sure. ? Yield= .63 grams

3rd time as a experiment ½lb . Ss pot
All went as planned, no misshaps from pulling
Pins to my filtered auric chloride in 4 hours, drooped the next morning and melted
Yield= .22 grams

 

[butcher]

The yields per pound are ranging all over the place, but it sounds like lose in the processes from boilovers and so on are a big reason.

Keep a stock pot (with some copper metal), anything you miss may be found there later.

As far as the stannous test, did you test the solution before adding the SMB, then after adding a portion of the SMB, and again after the solution went clear as the gold precipitated.

Too much SMB can give a false brown reaction, and if you only tested after precipitating the gold you do not have anything to compare it to, also a small amount of gold standard solution, so you can test your stannous chloride testing solution to see if it is reacting with gold.

If chorine was still involved in your solution when you added SMB, this can cause an overuse of SMB before the gold will drop, later testing this can give you the false brown reaction with your stannous chloride tests.

 

[Geo]

Rob, i noticed you mentioned putting a button in your solution. if you are using hcl/Cl, you dont have to do that and im not all that sure its going to help you anyway. from my experience, hcl/Cl has little effect of bulky solids. as a matter of fact, the larger the area, the better.if you are trying to get rid of the free chlorine, you can heat the solution or just wait longer and it will evaporate on its own. you add a button to AR solution to rid it of free nitric acid.

 

[Palladium]

After you filter the solution of nitric through the coffee filters do you let the solution of filtered nitric sit and then check the bottom of the bucket for sediment. Some times them foils get blown to powder and will travel through your coffee filters. Once you pour the solution through the coffee filters pour it through again. The first time will serve to plug any loose hole and the second time will catch the fine stuff. Could explain where your yield are going.

 

[Marcel]

Fully gold-plated IT contacts yield 0,2% at best
Partly gold-plated IT contacts 0,1% at best (Au and Pt)
Both results are from XRF using a button made of this material.
So if you deduct the typical losses, these results seem to be absolutly in range.
The only method that would make sense to me is the sulphuric cell. I havent tried it yet, but all other processes will be a waste of 98% of the material.
I would use the cell, take down the gold and sell the rest as copper scrap.

 

[ericrm]

Marcel
IT stand for what?

 

[etack]

Fully gold-plated IT contacts yield 0,2% at best

I don't believe that that is correct. the pins in his thread should be in the 2 g/Lb range.

fully plated back plane pins are in the 1% range

steyr223's pins are heaver small header pins or small back plane so they run less; but 2 g/Kg seems really low.


steyr223 if you can get some dimensions on your pins and run some surface area calculations on them.

They look to be in the 20-30 micro inch range. tho some are only plated 30 on the inside and 10 on the out.

In your nitric did they have full gold shells or something else?

What did you remove them from?

Eric

 

[steyr223]

Wow thanks guys
I will try to answer everyone's questions
it is difficult for me to read your post's whileI'm typing my post bare with me(phone)
Butcher another stupid (really) in my life
Thank you for pointing out the " nothing to compare it to" I will start testing
before, during, and after
Also I always thought I added the right amount of
smb "to much =false positive " oops

I can only type one small page on my phone
if I get below the line its ok until I make s mistake
and the phone wont let me see below the line
I will continue to next post

 

[steyr223]

Geo yes I was wondering why
it was aalmost always the same size
So no more nugget in hcl/bleach

Palladium no I was not it seems the 2nd time
I used nitric I had a filtering nightmare
I actually was wondering about that microscopic
golden flow, I mean Even after a double filter you can still see it while your pouring I considered it to be acceptable losses.

Marcel I will be getting back to you

Eric they come from machines that hold money
they don't give money (part of an ATM)

 

[steyr223]

Marcel what does IT stand for
you said xrf from a button made from this material ,Did you mean some pins directly melted and tested or a refined button

I have access to an xrf
what would give the most accurate reading.
A handfull of pins or a couple hundred melted together
I had melted 150 pins together heated for about 10 min ended with 21 grams. The xrf only registered zinc and ciooper.
I was not. There to see it
less than 1 or 2% may not have been enough for my jeweler to mention

 

[Smack]

Eric, IT stands for Information Technology, thats why you may have heard someone referred to as the IT guy or so and so works in IT. That's what it stands for here in the US anyway.

 

[ericrm]

ok thank you so IT pin, if i understand right refer to every pin that we enconter on normal basis... from cable,computer etc...

 

[Palladium]

Trust me that microscopic gold will add up real quick! Let the solution settle and drain the top part of after settling. That way you don't clog your filter until you get down to the bottom where you dump the thick stuff in at. It's probably the tin that's causing you problems. Once you get it all in a filter incinerate it and wash with hcl and it will filter well. Then ar or hcl/bleach.

 

[maynman1751]

Are you getting complete dissolution of the pins? Have you checked your used nitric solution with stannous to make sure no gold is dissolved there? I know, gold SHOULDN'T dissolve in nitric alone, but I would check! As a matter of fact, check all of your processing solutions with stannous. I can't tell you how much gold I was throwing away because I didn't let my solutions settle long enough before decanting. Now I keep all of my decanted (smb) solution in a separate container and I'm surprised at how much powder settles out. I also add my rinses to this so if there is any gold in solution it will drop out. Those tenths of a gram add up!

 

[butcher]

One of our members calls the stock pot a piggy bank, all of the little bits (missed) can add up to a nice fat little piggy.

 

[steyr223]

marcel i have never heard of a pin called IT . Me being from the good ole usa
I new IT stood for information technology but not for pins. thanks

It is difficult in my truck to let anything settle but i will try.
God i cant wait to get a lab

Thanks guys for all the info
I will do another pound in a few days
and leave it at a friends to settle and I will double filter and check everything with stannous

i am still curios what would be the best way to approach the xrf with pins
should it be melted the size of the window or just a cup full

What would give the most accurate readings?
THANKS STEYR223