Help needed in yield estimate telephone cards

[archeonist]

Hi guys,

I can get my hand on a extremly large amount of telephone cards, more than 29 thousand pieces.
I know the gold content of one single card is very low, but 29000 times a small amount could mean serious numbers.

Is it idiotism to buy these for 200 euro's (I do not count the labor for processing these, I know I have to cut all 29000 of them to get a fair amount in my beaker)
Let me hear what you guys would do please!

Best regards,

Erwin

 

[patnor1011]

As we say it is all here already
This may help answer some of your questions.

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=34&t=20572&hilit=sim+card

 

[archeonist]

As we say it is all here already
This may help answer some of your questions.

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=34&t=20572&hilit=sim+card

Thanks Patnor!

 

[patnor1011]

I would not go in this unless they are free.
Insane amount of work compared to possible return.
I would expect no more than 10g from amount you mentioned. Now try to estimate how long it will take to cut out plated area and chips out of 30k of cards. 8)

 

[archeonist]

Thanks for your advice patnor! Still I will buy them, just for the hobby :lol:

 

[Justincase]

Maybe use a drill press.
Clamp a large stack tight together and use a large diameter drill to drill out the entire stack at once.
The added advantage of braking them up and twisting so they will incinerate better.
Still more than lightly a negative in your return after all the work and chemicals.
with Two hundred euro you could buy 19g of scrap 375 alloy, or a nice sovereign if you shop around and find a keen seller.
That would give you profit with almost no work and a manageable bit of refining if you wanted , a much better use of your time.

 

[Barren Realms 007]

Maybe use a drill press.
Clamp a large stack tight together and use a large diameter drill to drill out the entire stack at once.
The added advantage of braking them up and twisting so they will incinerate better.
Still more than lightly a negative in your return after all the work and chemicals.
with Two hundred euro you could buy 19g of scrap 375 alloy, or a nice sovereign if you shop around and find a keen seller.
That would give you profit with almost no work and a manageable bit of refining if you wanted , a much better use of your time.

If you were going to try and drill the area out it would possibly work better if you get a bit that cuts a mortise joint used in wood working.

http://www.ebay.com/itm/14mm-Square-Hole-Saw-Mortising-Chisel-Twist-Auger-Drill-Bit-Woodworking-Tools-/151774444651?hash=item2356763c6b:g:yTAAAOSwLVZVzgwj

 

[Justincase]

Maybe use a drill press.
Clamp a large stack tight together and use a large diameter drill to drill out the entire stack at once.
The added advantage of braking them up and twisting so they will incinerate better.
Still more than lightly a negative in your return after all the work and chemicals.
with Two hundred euro you could buy 19g of scrap 375 alloy, or a nice sovereign if you shop around and find a keen seller.
That would give you profit with almost no work and a manageable bit of refining if you wanted , a much better use of your time.

If you were going to try and drill the area out it would possibly work better if you get a bit that cuts a mortise joint used in wood working.

http://www.ebay.com/itm/14mm-Square-Hole-Saw-Mortising-Chisel-Twist-Auger-Drill-Bit-Woodworking-Tools-/151774444651?hash=item2356763c6b:g:yTAAAOSwLVZVzgwj

That may work.But I have found that trying to drill plastic with woodworking bit's can be a pain.plastic likes a much shallower cutting angle than most wood drills.
If you could fit a conventional bit in the woodworking dril sheath that would be quite a neet cut.

 

[archeonist]

Guys, no drilling needed. I bought the lot today for a much better price. These cards are about 13 years old. I noticed that the glue, wich holds the chip in place, has aged. When bending a card the chip pops right off! A lot of them I can almost do in one second.
Still a hell of a job, but a lot less plastic. At the end that will give me a higher yield I hope.
I'll try to keep you guys informed during this project.

 

[Justincase]

Guys, no drilling needed. I bought the lot today for a much better price. These cards are about 13 years old. I noticed that the glue, wich holds the chip in place, has aged. When bending a card the chip pops right off! A lot of them I can almost do in one second.
Still a hell of a job, but a lot less plastic. At the end that will give me a higher yield I hope.
I'll try to keep you guys informed during this project.

good stuff.
Make sure to search properly for embedded chip's and bond wires,they may be as much as the plated front.
Hope the whole pack came out in one.
You will no doubt be going for acid digestion rather than adding it collector metals and smelting,as everyone tries at first.
Do not try to filter your solution,be very patient and let everything settle a day or two if need be.your gold will lightly be extremely finely divided.
Do not fall into the trap of "aspirational Refining"you do not know the yield until you have run your material with your available kit and resources.
Good luck even though I ran a test batch of several hundred T-Mobile cards.You never know until you test!
But it is best to test in small samples before you buy the whole cow.
J

 

[archeonist]

Hi J,

They come out like in the picture, they pop out easy. Still only done 2000, so 27000 to go :shock:
What should I do? First run in AP like fingers, collect the foils and incinerate the rest? What will the route be after incineration? Panning the gold wires?

 

[patnor1011]

That is exactly how I did them.

 

[Justincase]

You can determine the thickness of gold plating by Using a pencil eraser and counting the strokes to cut through the gold. But I can see it is quite light in colour in places and the nickel sub strata is showing through a bit so that is more than lightly thin flash plating.
This test is not very accurate ,but you can tell the difference between flash gold and thick gold plate. flash come's off in one two or three strokes the more stork's the better you have done. some will not come off easily and that is more like layered gold which is what I look for.
You do not want to use etching solution's if the plating is to thin to hold together in manageable particles.
What I do with my I.C.'s is incinerate and pulverise, then use up some 1940's coin stock as a collector and smelt them.
It is still to dilute an alloy to recover economically so I then use that alloy when I inquart my next batch of Karat gold. It is not very good if you want any return figures. but it adds the value to your output with only an hour or two hot work.
One of the reasons that people shy away for buying such items is that the flash plating is so thin it is swamped by the other metals.
The easiest rout though the less efficient is to incinerate and pulverise . then base metal leach before digestion in A.R.
Very messy and time consuming as the Au will be so fine as to make filtering near impossible so you will have to depend on settling your sediment.
quite costly in acid as well.
I have never used a shaker table but I have wanted to run some test's to see if that would let you concentrate the metals before smelting, Always more kit to build and test's to run.
I would be very keen to hear if some one has a better way or one that can turn a profit from such thin picking's.

 

[patnor1011]

That visible plating is only small bit of total recovered. Majority comes from bonding wires on other side of that chip.

 

[archeonist]

That visible plating is only small bit of total recovered. Majority comes from bonding wires on other side of that chip.

Yes patnor, I noticed that. There are a few that have a transparant epoxy on the backside, more visible gold there.

@justincase, as I understand you recommended an extraction technique? So when I have my powder from incineration , I mix this with the molten metal (from coins), inquart and process using nitric? Never done this. What dissolves (won't actually dissolve but mix) the gold better, is it copper or silver?

I'll do 2 test batches, partnor's way and yours.

 

[Justincase]

If you have familiarised your self with the basic processes you would understand that some metals act as a solvent and soak up elements of interest. Silver and Copper are the two most used but aluminium and others are used in other situations.
Impurity's such as silicon and other ceramic's will be tied up in your flux which can be ladled of the top if need be before poring.
Do not go " Mixing with Molten Metal " as to introduce cold and possible moisture containing material to molten metal would cause a Steam Explosion!!
I mix every thing together evenly as possible dry and charge my crucible half way before starting to heat. But as I say this will collect just about 99% of your value which is not a lot.
To make it more economical I then use that alloy for Karat scrap.
If you have read Mrs Hoke and preformed her excellent acquaintance exercises this will all be quite easy for you.
If you have not you will be trying to reinvent several hundred years of trial and error with material not well suit to experimentation.

 

[archeonist]

If you have familiarised your self with the basic processes you would understand that some metals act as a solvent and soak up elements of interest. Silver and Copper are the two most used but aluminium and others are used in other situations.
Impurity's such as silicon and other ceramic's will be tied up in your flux which can be ladled of the top if need be before poring.
Do not go " Mixing with Molten Metal " as to introduce cold and possible moisture containing material to molten metal would cause a Steam Explosion!!
I mix every thing together evenly as possible dry and charge my crucible half way before starting to heat. But as I say this will collect just about 99% of your value which is not a lot.
To make it more economical I then use that alloy for Karat scrap.
If you have read Mrs Hoke and preformed her excellent acquaintance exercises this will all be quite easy for you.
If you have not you will be trying to reinvent several hundred years of trial and error with material not well suit to experimentation.

Yep, I know, I have read parts of Hoke and learned a lot. Never read the part for making a flux though, I Always read the parts that were accurate for my processes. But I will read that part. For my work as a Chemistry teacher I learn a lot about this kind of chemistry in practice. I use this information to make chemistry a lot more meaningfull for my students, and that works!
Thanks for the tip about the moisture, could have been a sad end of a great hobby..

 

[Justincase]

Mrs Hoke has produced an excellent tutorial and much like when you are teaching your students it is important to stick to the lesson plan.
There is quite a deep logic to the sequence of study.
It helps a lot with understanding how the dispirit information can come together into an logical process and help you decide when and where to use each tool.
I am surprised that a Chemistry Teacher has not studied how metal alloys and amalgams work.
Where are you, In my younger day's we use to take weekend in Rotterdam. There where some great clubs hidden in it's industrial district's.
But have not had time for a holiday for over ten years. :lol:

 

[modtheworld44]

archeonist

If these were mine,I would use my 12 inch cullender and polypropylene filter cloth and HCL/bleach leach the plating.Then Incinerate and pan bonding wires,time spent doing it this way would be about 8 hours vs 1-2 days using other chemical process.Thanks in advance.



modtheworld44

 

[Justincase]

archeonist

If these were mine,I would use my 12 inch cullender and polypropylene filter cloth and HCL/bleach leach the plating.Then Incinerate and pan bonding wires,time spent doing it this way would be about 8 hours vs 1-2 days using other chemical process.Thanks in advance.



modtheworld44

Easy enough to test. Try 500.
Note the amount of leach it took and the time to filter and so forth.
Then simple math's will tell you how much recovery you get for how much liquor you have to handle.
My personal preference is to do one process that catches every thing possible first time instead of having to do two separate recovery's.
My panning is a little rusty to be going after supper fine Au and the bond wires are prone to making some very find particles when pulverised. I would want a good large table to insure as little loss as possible.
Doing a side by side comparison of each possible scenario would be informative and let you compare effective results.