IC chips gold recovery

[Liquidau]

Please elaborate Kurt. Why is the blue bowl so bad? BTW I have not had success with it either, but I’d love to know the pitfalls you have experienced….Thanks.
Len

 

[kurtak]

Please elaborate Kurt. Why is the blue bowl so bad? BTW I have not had success with it either, but I’d love to know the pitfalls you have experienced….Thanks.
Len

First of all & right out the gate you have to feed a blue bowl extremely slow - you can actually pan with a regular gold pan faster then a blue bowl - by a lot

With a gold pan (depending on the size of the pan & how good you are with a pan you can pan about 1/2 cup to 1 cup of starting material to a concentrate in about 10 or 15 minutes

Thats because with a pan you can shake the pan back & forth &/or tap the side of the pan (hard tapping) with your hand causing the heavies (gold) to move down in the material - leaving you with a gold free layer on top of the material which can then be washed off relatively quick &/or aggressively - it is of course a repeat shake down wash off process but can be done relatively quick

now then - before moving on to the blue bowl - it is important to understand that in fine milled chip ash/carbon that besides the bond wires there are other heavies in the carbon/ash --- fillers used in the epoxy & & fine bits of the silicon die (created during milling) --- in panning those heavies going to the bottom of the pan along with the bond wires (due to the shaking & tapping) making up you concentrates

How a blue bowl works (at least in theory) is with an incoming flow of water - from the outside of bowl - that swirl's around the bowl - moving to the center of the bowl (where the cone is) - BUT - the water flow has to be adjusted (in theory) such that it will leave the heavies deposited across the bottom of the bowl &/or at the bottom of the cone while lifting the lighter material up the side of the cone & out the hole at the top of the cone

As a side note; - this may work well with "fine" placer gold &/or fine milled ore - I don't know because I have only used it for chip ash/carbon - which acts different then placer/ore --- (to be explained)

So - with chip ash/carbon (milled & sifted to 80/100 mesh minus) in a blue bowl this is what happens

First of all - you can not just put a 1/2 cup to 1 cup ash/carbon in the bowl - that because it will "load" the bowl with material (both heavy & light) & at first just the light stuff will go across the bowl & up & out the cone - but then a layer of heavies will develop on top of the material preventing the flow from washing the light material under that layer of heavies basically stopping the washing process --- if you turn the flow up to move the top layer so the flow can get to lighter material under it - then the flow is strong enough to push those heavies up & out the cone --- & there goes your gold

So - first you have to have a flow set that will move the light material without moving the heavy material AND you have to feed that material very slowly - like a teaspoon or less at a time so the flow has time to wash the light material way --- which is all fine & dandy at first BUT as more material is added (slowly) the heavier material slowly moves across the bowl to the cone & a few thing start happening

the build up of the heavies start creating a resistance to the lighter stuff moving across the bowl & that resistance starts causing the heavies to push across to the cone along with the lighter stuff - which will cause the small surface area round the cone to become "loaded"

Once loading at the cone happens it will start to cause heavies to go across to top of the "loaded" material & up & out the cone along with the light stuff --- you can sit there & watch bond wires go up & out the top of the cone once you get loading at the bottom of the cone

Loading will start happening after about 1/2 cup to 2/3 cup material & because of slow feed speed that will take an hour or more - at which time you have to shut it down to clean the bowl & start again

To clarify --- to much water flow & heavies go out the bowl right out the gate with the light stuff --- to little flow the bowl loads with both heavy & light causing above problems - get the flow just right & it is still just a matter of time to loading & clean out

Now then why are bond wires (chip ash/carbon) different the placer/ore ?

Because when milling chips - the wires tend to twist & bend - being twisted & bent allows water to get under them & lift them allowing them to roll & tumble across a slick surface (like a blue bowl) &/or the surface of built up heavies (which is why wires start going with the light stuff once the bowl is loaded)

With a pan the wires shake/tap down giving you a gold free layer/zone to wash off

on a concentrator table you have ribs in the mat the wires come up against to stop the roll/tumble of the wires

even with a table - once it is loaded - you have to stop for clean out - or gold (wires) will roll/tumble across the top & out the end - BUT - you can build (or buy) a table with a much larger surface area then a blue bowl & therefore feed much fast & run much more material before clean out

IMO - the blue bowl I bought when I first started was one of the worst investments I ever made --- it only took about 3 - 4 days of trying to use the blue bowl to figure out that I could pan more material faster by going back to my good old gold pan - & building a table was a big step up from that

IMO - & based on my personal experience when it comes to concentrating chip ash/carbon - listed from worst to best the list is as follows

ribbed drain pipe (cut in half) don't even think about it

blue bowl - just not worth it

gold pan - good for 5 - 10 pound batches

concentrator table with good surface area (not shaker) - really want/need it for over 10 pound batches

actual shaker table - the best

Kurt

 

[sayf]

First of all & right out the gate you have to feed a blue bowl extremely slow - you can actually pan with a regular gold pan faster then a blue bowl - by a lot

With a gold pan (depending on the size of the pan & how good you are with a pan you can pan about 1/2 cup to 1 cup of starting material to a concentrate in about 10 or 15 minutes

Thats because with a pan you can shake the pan back & forth &/or tap the side of the pan (hard tapping) with your hand causing the heavies (gold) to move down in the material - leaving you with a gold free layer on top of the material which can then be washed off relatively quick &/or aggressively - it is of course a repeat shake down wash off process but can be done relatively quick

now then - before moving on to the blue bowl - it is important to understand that in fine milled chip ash/carbon that besides the bond wires there are other heavies in the carbon/ash --- fillers used in the epoxy & & fine bits of the silicon die (created during milling) --- in panning those heavies going to the bottom of the pan along with the bond wires (due to the shaking & tapping) making up you concentrates

How a blue bowl works (at least in theory) is with an incoming flow of water - from the outside of bowl - that swirl's around the bowl - moving to the center of the bowl (where the cone is) - BUT - the water flow has to be adjusted (in theory) such that it will leave the heavies deposited across the bottom of the bowl &/or at the bottom of the cone while lifting the lighter material up the side of the cone & out the hole at the top of the cone

As a side note; - this may work well with "fine" placer gold &/or fine milled ore - I don't know because I have only used it for chip ash/carbon - which acts different then placer/ore --- (to be explained)

So - with chip ash/carbon (milled & sifted to 80/100 mesh minus) in a blue bowl this is what happens

First of all - you can not just put a 1/2 cup to 1 cup ash/carbon in the bowl - that because it will "load" the bowl with material (both heavy & light) & at first just the light stuff will go across the bowl & up & out the cone - but then a layer of heavies will develop on top of the material preventing the flow from washing the light material under that layer of heavies basically stopping the washing process --- if you turn the flow up to move the top layer so the flow can get to lighter material under it - then the flow is strong enough to push those heavies up & out the cone --- & there goes your gold

So - first you have to have a flow set that will move the light material without moving the heavy material AND you have to feed that material very slowly - like a teaspoon or less at a time so the flow has time to wash the light material way --- which is all fine & dandy at first BUT as more material is added (slowly) the heavier material slowly moves across the bowl to the cone & a few thing start happening

the build up of the heavies start creating a resistance to the lighter stuff moving across the bowl & that resistance starts causing the heavies to push across to the cone along with the lighter stuff - which will cause the small surface area round the cone to become "loaded"

Once loading at the cone happens it will start to cause heavies to go across to top of the "loaded" material & up & out the cone along with the light stuff --- you can sit there & watch bond wires go up & out the top of the cone once you get loading at the bottom of the cone

Loading will start happening after about 1/2 cup to 2/3 cup material & because of slow feed speed that will take an hour or more - at which time you have to shut it down to clean the bowl & start again

To clarify --- to much water flow & heavies go out the bowl right out the gate with the light stuff --- to little flow the bowl loads with both heavy & light causing above problems - get the flow just right & it is still just a matter of time to loading & clean out

Now then why are bond wires (chip ash/carbon) different the placer/ore ?

Because when milling chips - the wires tend to twist & bend - being twisted & bent allows water to get under them & lift them allowing them to roll & tumble across a slick surface (like a blue bowl) &/or the surface of built up heavies (which is why wires start going with the light stuff once the bowl is loaded)

With a pan the wires shake/tap down giving you a gold free layer/zone to wash off

on a concentrator table you have ribs in the mat the wires come up against to stop the roll/tumble of the wires

even with a table - once it is loaded - you have to stop for clean out - or gold (wires) will roll/tumble across the top & out the end - BUT - you can build (or buy) a table with a much larger surface area then a blue bowl & therefore feed much fast & run much more material before clean out

IMO - the blue bowl I bought when I first started was one of the worst investments I ever made --- it only took about 3 - 4 days of trying to use the blue bowl to figure out that I could pan more material faster by going back to my good old gold pan - & building a table was a big step up from that

IMO - & based on my personal experience when it comes to concentrating chip ash/carbon - listed from worst to best the list is as follows

ribbed drain pipe (cut in half) don't even think about it

blue bowl - just not worth it

gold pan - good for 5 - 10 pound batches

concentrator table with good surface area (not shaker) - really want/need it for over 10 pound batches

actual shaker table - the best

Kurt

thank you very much kurt, i carefully used your instructions step by a step and this time i got 14 grams of gold out of 10 kilo grams of IC chips , i incinerated the ic chips in a furnace and powdered them using a small ball mill then i sieved powder and collected the ash , i run a weak magnet on the ash to get rid of the kovar and gave the powder a wash in nitric acid before washing it with water , every thing went great and 1.4 grams of gold per kilogram of ic chips is an expected outcome .
can you give us some information about your concentrator table i think am gonna make one as it looks very great for big patches ?

 

[snoman701]

i run a weak magnet on the ash to get rid of the kovar and gave the powder a wash in nitric acid before washing it with water , every thing went great and 1.4 grams of gold per kilogram of ic chips is an expected outcome .

You are processing the kovar legs as well right?

 

[sayf]

You are processing the kovar legs as well right?

i processed the silicon dies with the concentrate in the final aqua regia step , and ill of course process the kovar legs when i get a big quantity.

 

[snoman701]

Just put the kovar legs in your waste acid.

 

[Liquidau]

Thanks Kurt. Terrific explanation as usual. Back in the box it goes.
Do you have an opinion/experience on the Gold Cube? Supposed to manage a quite large volume of material, that’s not necessarily classified to 80 mesh (although that should help)?

 

[sayf]

Just put the kovar legs in your waste acid.

Great idea

 

[FriscoDad]

ribbed drain pipe (cut in half) don't even think about it

blue bowl - just not worth it

Hi @kurtak
Thank you for your detailed explanation of the deficiencies of the blue bowl when recovering gold from IC chips.
Can you provide some background as to why you dismiss the ribbed drain pipe? Is it similar to the limitations of the blue bowl, too slow and labor intensive? I saw a youtube where a guy created an automatic system to feed the concentrate into the water flow so he didn't have to sit there and feed it in manually teaspoon by teaspoon.
Or are there other reasons?

Edited for a typo.

 

[kurtak]

Can you provide some background as to why you dismiss the ribbed drain pipe?

Because a pipe (whether ribbed or not) has a very narrow surface area (1/2 to 1 inch wide) once that narrow surface area becomes "loaded" EVERYTHING (including bond wires) just starts washing over the top & past the sides - that loading - on a very narrow surface area happens very quickly

There is a reason sluice boxes & concentrator tables are made with a wide flat surface & NOT a round surface

Kurt

 

[Rreyes097]

First off - if you are processing "a good mix" (all types) of ICs you should most certainly get MUCH more the 4 grams gold from 20 kg chips

To put it in perspective - if you processed NOTHING BUT 20 kg of PROMS (the very lowest grade of chips) then yes you would only get (about) 4 grams

But a true "mix" of chips should give you better (much better) results

This thread should give you "an idea" of what to expect from "each type" of chip(s)

https://goldrefiningforum.com/threa...ic-types-of-ic-chips-flatpacks-and-bga.22951/
That said ------


Per the bold print - this IMO (In My Opinion) is your first mistake !!!

You first NEED to get rid of the base metals BEFORE washing of the ash/carbon (after incinerating & milling/crushing) --- as well as larger pieces of broken silicon dies

If you don't get rid of the Kovar &/or copper legs/wires (as well as silicon dies) in the carbon/ash BEFORE trying to wash off the carbon/ash - those Kovar/copper legs/wires & large pieces of silicon dies will cause interference in the washing process which will in turn cause the VERY fine gold bonding wires to wash off along with the carbon/ash

So the proper steps are as follows ------

1) incinerate to turn the epoxy to carbon/ash

2) mill/crush the carbon/ash (incinerated chips) to fine powder

3) sift the milled chips (carbon/ash) through (at least) 80 mesh (or 100 mesh) screen which will remove the "larger" Kover/copper & larger pieces of silicon dies --- smaller Kovar/copper wires (& fine crushed silicon) will go through the sifting screen - so -----

4) spread out the (fine milled) carbon/ash in a very thin layer & run a "weak" magnet over it to remove any Kovar that made it through the sifting screen --- there will still be fine copper in the carbon/ash which you need to get rid of

Depending on how much copper is in carbon/ash you may have to ---------

1) leach/dissolve the copper out of the carbon/ash BEFORE washing the carbon/ash off to collect/concentrate the gold bond wires --- or ------

2) you MAY get away with doing a "pre-wash" of the carbon ash - to "reduce" the amount of carbon/ash before leaching/dissolving the copper - then a second wash to collect/concentrate the bond wires

There are a couple different method to the above step 2 depending on the amount of copper in the carbon ash

Bottom line - you want to get rid of as much "junk" from the carbon/ash BEFORE washing the carbon/ash to concentrate the bond wires for final leaching or smelting

The trick is leaving the gold in the carbon/ash during the process of removing the junk

if you don't remove the junk (at least the LARGE Kovar/copper/silicon) you will most certainly wash gold (bond wires) out with the carbon/ash

Kurt

Kurt I could really use your help. Going back and forth on these threads are not helping me understand all of the information. I just incinerated a few BGA chips and a lot of RAM DDR 2 chips. Also there were a few chips that did contain legs. I didn't process a lot because I'm still trying to figure out the whole process and do it correctly thus far I have incinerated them and then used a coffee grinder to grind them down. Then I sifted them through a basic sifter kitchen sifter? Now I'm not sure what I'm doing for next. I'm sitting over the fine sifted Ash and stuff pulling out visible wires but some of them look to have gold on them aren't they supposed to stay in? The only other time I did Ic chips was a bunch of the same ddr2 no legs on the chips style. The problem then was my incineration, it wasn't good enough but when I did incinerate them enough I was able to pull out all the gold and things are great but this has some of that the same chips along with a couple mixed ones with legs in it. I started to run a weak magnet over it but was afraid that I was pulling up gold bonding wires that were attached in the mix so I stopped that and I just started pulling out visible wires. But like I said these wires don't look to be just copper some of them look to have gold on them or maybe it's the trick of the light I don't know I've read a bunch of threads on how to do this and I thought I didn't know how to do it but I don't know what's wrong I think I'm just confused if you can offer any help one-on-one that would be great if not I understand thank you very much.

 

[J.Najam]

Hello all,

These are some remains of the IC chips (post entire procedure, non chemical, sluiced panned etc.) and there seems to be some sort of gold holding out on the bottom of it. How is it suggested to treat these? very hard to recover these by panning anymore as the concentrates are so fine, they tend to drag along the impurities with them. Also, what exactly is the material that I'm looking at?

Thanks

 

[Yggdrasil]

Hello all,

These are some remains of the IC chips (post entire procedure, non chemical, sluiced panned etc.) and there seems to be some sort of gold holding out on the bottom of it. How is it suggested to treat these? very hard to recover these by panning anymore as the concentrates are so fine, they tend to drag along the impurities with them. Also, what exactly is the material that I'm looking at?

Thanks

The picture do not allow zooming clearly, so it is hard to say what it is.
You can incinerate again so *** ashes completely.
Thgen you will have only ashes and what ever bonding wires are left.

 

[J.Najam]

The picture do not allow zooming clearly, so it is hard to say what it is.
You can incinerate again so *** ashes completely.
Thgen you will have only ashes and what ever bonding wires are left.

That's the issue, not sure if I'm looking at bonding wires or no. Ill transfer these to a beaker then share an image from the bottom

 

[J.Najam]

Here , maybe it could help to figure

 

[Martijn]

Do you have a jewelers loupe? you need one or a microscope to see one single wire. these pictures are not even clear enough to see the grains of 'sand?'

 

[J.Najam]

microscope, im not so sure if ill get one cheap enough, and I don't have a jewelers loupe ill get one then

 

[Yggdrasil]

Here , maybe it could help to figure

Anyway how it is, if there are something or not.
It is quite obvious that it is not sufficiently ashed, too much black stuff.

Edit for spelling

 

[Martijn]

microscope, im not so sure if ill get one cheap enough, and I don't have a jewelers loupe ill get one then

Ordered my microscope for 15 euro with USB connection to show on a pc screen. Works more than good enough for me
A jewelers loupe is a must have in e waste recovery. If only for those tiny model & part numbers. For jewels... well kind of obvious, right?

 

[J.Najam]

Anyway how it is, if there are something or not.
It is quite obvious that it is not sufficiently ashed, too much black stuff.

Edit for spelling

Ill retry panning it out first then, if it doesn't work well.. will go with drying it out completely and then incinerate it in my graphite crucible.

A jewelers loupe is a must have in e waste recovery.

This is the first time im reading of its importance. Other threads that I have gone through about the ICs (especially by KURTAK AND PATNOR), didn't realize that it is actually part of the process and not just passion.

Definitely adding either of these aforementioned equipment to my arsenal.

Thanks to you both!